[2.0.x] Backport fixes

[jtojnar]

We will want to release 2.0.2.

Need to go through all the changes on master (ignoring translation updates) and determine if they are backport worthy. Marking with ❔ the issues I was unable to reproduce in 2.0.1 but probably should be backported. Suspected cherry-picks in parentheses.

• c066c2a Add OARS rating to appdata (3686202)
• 937ed67 appveyor: upgrade env separately [skip travis] (2fe44ef)
• de0ca9b Py3: use a string as the 1st argument to exec [skip ci] (16d346d)
• f254bb2 appveyor: update version field [skip ci]
• 34060e2 ci: use openmp in windows libmypaint build (f49f0e5)
• 0d2995d Add softness parameter to draw_dab call
• b3a9e66 i18n: fix key error in German translation (a553576)
• 0ada665 i18n: fix key errors (translated brace variables) (a553576)
• 321a54e i18n: use square brackets in report template (1f7f9f9)
• b1676a4 windows: amend delete patterns [skip travis]
• edce621 ci: set appveyor clone depth to 1 and fail early
• f73c91a ci: skip 32bit builds unless C++ code has changed
• be7b04b ci/windows: delete unused icons [skip travis]
• 304ccbc windows: don't bundle txt/pyc files [skip travis]
• d05acf2 ci: skip windows builds for non-related changesets
• 68dc8fb windows: exclude unused icons
• e9f0455 windows: exclude unused pacman files [skip travis]
• 63981d6 windows: exclude more unused DLLs [skip travis]
• 5956ec2 windows: exclude unused python libs [skip travis]
• 8f0080c i18n: mark clearly incorrect translations as fuzzy (33fa0a8)
• 4c617b4 i18n: rewrite .po template update script (33fa0a8)
• f5eadcb i18n: update .pot and .po files (33fa0a8)
• 3e1dc51 i18n: finish removal of intltool usage (33fa0a8)
• 93c43b5 Store #translated, not %translated, in cache (33fa0a8)
• d04a681 Fix travis CI (intltool still required)
• 89511f7 setup: enable msgfmt checks [skip appveyor] (33fa0a8)
• 19648e9 setup: improve po check error message [skip ci] (33fa0a8)
• b665173 svg icons: fix xlink namespace not being specified
• f0d174d svg icons: fix missing xlink namespace [skip ci] (9a1ed51)
• 1f03428 Add layer-move icon to icon sheet (svgz) [skip ci] (9a1ed51)
• 425afe2 Fix misc. typos in documentation/comments [skip ci] (8598f44)
• 1cc5a96 Clean up icon sheet
• ed08412 Update icon extraction script
• f1ec704 Remove obsolete icon (previously renamed) (9a1ed51)
• bc47f42 Export optimized icons from sheet (9a1ed51)
• ee59638 Fix rounding in conversion to rgba8 while saving (7abfa98)
• 650fc3e Restructure icon sheet (9a1ed51)
• 601673f Rewrite the icon export process (9a1ed51)
• 3dc54e4 Extract icons
• 9d0ca85 Remove unused icons [skip ci] (a528789)
• 7bb78de Optimize color selection icons [skip ci] (e442af7)
• a5bd2bd Add option to disable hardcoded fallback key binds
• 8609ae1 i18n: update translation files
• 4fe84d8 Remove unused icons [skip ci]
• 0aa7b69 io: fix brush groups encoding bugs (Windows) (580ca45)
• a18f088 meta: fix tag check, clarify use of prerel numbers (e621ab3)
• d6a6021 flake8: fix a few warnings in lib/meta.py (5fe84eb)
• 984ded6 Py2: fix 2.7-incompatibility in previous bugfix
• 7478efa Use collections.deque for undo/redo stack (1d0a185)
• ff36dfe Make the size of the undo stack configurable (ecfdd6f)
• 72332b1 Validate value for the size of the undo stack (b440cb2)
• 90f9a19 Increase default undo stack size from 30 to 40 (46baabc)
• 5feb516 Added financial contributors to the README (cd76b5c)
• dd141b6 CODEQUAL: fix docstring type hints (and imports) (7b0a69a)
• 22919d9 Fix errors in imports (2fb4d04)
• 14426df Make nosetests runnable for individual modules (c8b8d72)
• d151385 Update stroke_to call to account for linear sRGB (f15f4a8)
• fdfed8b Add option to start up and then quit after a delay (9c9b220)
• edc77e6 Remove distutils as runtime dep. [skip appveyor] (50bf772)
• 96b6398 setup.py: add ability to pass arguments to demo (d9b6d3f)
• 2e9810d ci: run demo as part of the windows tests (3c3c427)
• fdcee9c ci: run demo as part of travis tests, using xvfb (213041f)
• ac5e6d2 doc: list librsvg as a dependency (runtime) (eb37e4c)
• 1aa0223 Rename gichecks -> gibindings, to use as proxy (c1ae54a)
• 8c7015e Import all gi bindings via lib.gibindings (26157d7)
• 091a962 i18n: fix access to libmypaint message catalogs (fd3ef8e)
• b585239 Fix PEP8 warnings (b3dcf3d)
• 1b64ef1 hound: ignore 'black would make changes' [skip ci] (116856e)
• 67d57e9 meta: refactor prerelease values and allow '-rc' (1bf3c70)
• f41eec2 Add Discord Badge [skip ci]
• 2852a9b Fix markdown syntax [skip ci]
• b6648a9 README: fix whitespace issue [skip ci]
• 96202d5 README: fix missing bracket (d'oh) [skip ci]
• 3191ab6 Fix Markdown Syntax Issue [skip ci]
• f7b979d And Finally remove extra bracket...[skip ci]
• 893ecb2 tests: fix image slice count in non-Windows tests (9148f5c)
• ec11b1b Fix failing DocPaint tests (42438e9)
• ab7419f externalapp: restore env for launched processes (e5d92d3)
• d54d8ba msys2: upgrade pacman before update [skip travis] (8b4b9a7)
• 808610d msys2: add missing --noconfirm [skip travis]
• af63b67 ci: fix msys2 update in Windows ci [skip travis] (655371b)
• 97b728d Define _DARWIN_C_SOURCE on Darwin [skip ci] (c1ff5f8)
• 368862d Fix HoundCI config [skip ci] 7f98989
• 66b2ba9 Py3: Fix drag-n-drop file opening
• 03dca81 Make image type specifiable for pixbuf loading
• eaafc10 Expect svg data when loading vector layers
• 4b474ab Update all HCY adjusters when gamut mask changes
• 918751e Link to <=1.1 to >=1.2 migration instructions [skip ci]
• b5153b9 Add angle param to set_symmetry_state
• 2dd96ef Add symmetry angle adjuster to options panel
• 73776d5 Add general line intersection function
• ed241fc Add line + polygon intersection function
• 515c2fc Fix symmetry lines getter
• 62121e0 Add nearest-point-on-segment function
• 1b45356 Add function for nearest-point-in-convex-polygon
• 90c6eeb Add nearest-point-on-line function
• bfab5b3 Rewrite cursor-for-angle function
• 7d95cfa Rewrite & amend symmetry state, overlay & editing
• a9a9267 Fix pos access in two instances of drag_start_cb
• 2b31860 Prioritize input widgets for keyboard events
• dcd8c6d Ignore keyboard events in layer list
• 47d4aa4 Update copied add_metaclass decorator
• 9dd2bac Add focus-clearing to ToolStackWindow/BrushEditor
• 6a2f91a Add slider with keyboard input (InputSlider)
• 31a072a Replace most GtkScale instances with InputSlider
• 0c722d2 Add dynamic tooltips to InputSlider
• 31088ee Use setting tooltips for shared brush tool options
• 8e849a6 Py3: fix url unquoting and remove quoting helper
• d43ea25 Fix format spec errors in pt/zh_TW translations
• aaae3e6 Expose indexed access to mode stack
• 8e8b66c gui.mode: clean/fix initial_modifiers handling
• 13c6eb9 Split out brush radius approximation calculation
• 521a828 Improve performance of last-event recording
• d5eab94 buttonmap: use mode's get_name as label fallback
• 12195c7 Add canvas-drag brush resizing
• 7df8696 brush resize mode: revise handle positioning
• 7fe386a brush resize mode: fix small bugs, clean & comment
• 609a3b9 Semi-revert previous last-event recording change
• 8689ca7 gui.symmetry: replace center coord. input widgets
• 824de8f gui.fill: improve overlay redrawing
• 0ab6f4e lib.helpers.Rect: remove deprecated method aliases
• ffbfca2 lib.helpers.Rect: add new utility methods
• 678a7c8 gui.mode: add method popped to InteractionMode
• 417f440 gui.symmetry: refactor to improve gui performance
• 1ccb541 gui.symmetry: change line styles for axis lines
• 187dbd2 gui.symmetry: queue axis updates when editing
• 252891f gui.mode: add ev_x, ev_y to drag_update_cb
• 1849559 gui.mode: speed up motion_notify_cb
• cdfe439 gui.device: fix _init_device_settings call order
• 914160f gui.document: cache top mode for motion_notify_cb
• e981791 Switch to newer appveyor build image [skip travis]
• 21a8562 Fix switching to BrushResizeMode from line modes
• 27b5809 inktool: fix drag_start_cb crashing on space-drags
• 75c2939 inktool: prevent strokes for buttons other than 1
• eeb1dd4 CODEQUAL: rewrite action whitelist conditionals
• 1bfc81c gui.colorpicker: remove unused attributes
• 706af78 HCYColor: keep chroma when converting to/from HSV
• 9cc92eb gui.colorpicker: refactor hcy-component picking
• d682555 gui.colorpicker: mitigate lag on drags
• da4da88 README.md: add info about winget package [skip ci]
• 49c739e README: add clarification about winget package
• 83418db gui.topbar: fix args in call to Gtk.Menu.popup
• 9e81378 Fix hound config [skip travis] [skip appveyor]
• 91500a7 gui.linemode: move line ends when pressing ctrl+shift
• 5b9770a Revert HoundCI config to original state
• b812965 lib.feedback: use functions instead of properties
• 2fda646 gui.framewindow: replace size/dpi button+dialog
• 8336cea gui.frametool: use enum, not str, for performance
• db7089f gui.framewindow: refactor frame positioning
• 6885dfc gui.frametool: queue frame adjustments
• 6e64d5f gui.frametool: improve redraw performance
• 284dc00 gui.symmetry: fix redraw glitch on axis adjustments
• 19b10b9 gui.document: refactor/optimize undo/redo updates
• 3e5dd85 lib.command: limit command stack update event
• c84684d Fix use of wrong ui string in undo/redo [skip ci]
• 47903f5 BUGFIX: fix wrong use of fraction after update
• 8292199 gui.framewindow: defer hq rendering when dragging
• fdbcdb9 Remove reference to non-existent Gdk.EventGrabBroken time attribute
• e7748e1 fix dimming of main window after dismissing recover backup window
• 8c72337 Fix formatting in Malay translation
• 08bc044 Update changelog for 2.0.1 (4d91b31)
• 4429d78 Acquire/release the GIL while processing tile requests (356716e)
• c0b7ea0 gui.windowing: remove UTILITY hint from SubWindow
• 61984cc mypaint.py: break out check for old config
• 60f3f83 setup.py: refactor some minor things
• d306dab Refactor module & resource path setup/handling
• 97e8aa7 Windows: fix & rework PKGBUILD bundling/handling
• a00ce2d Add info about customizing installation layout
• b3ae755 Merge PR Lib path refactoring #1109 from jplloyd/lib-path-refactoring
• 22d7982 l11n: handle exceptions caused by "invalid" locales
• 41415d0 i18n: add entry for Central Atlas Tamazight
• 506b10d Change Paste so it always pastes to a new layer
• fc63fe1 Rework paste positioning
• 5752880 gui.document: fix copy bbox & add legacy setting
• 51bb04b gui.accelmap: fix search in keyboard map
• a03d19e Update changelog [skip ci]
• fdbfd86 gui.picker: handle touch events in click handler
• 89cca8c docs: fix simple typo, retrieveing -> retrieving
• 453f4e8 Merge typo fix [skip ci]
• dafe3b7 cursor: inter. testing - fix shadowing warnings
• a2decae cursor: add optional dynamic crosshair to brush cursor
• 41d6bff add preferences for dynamic brush cursor crosshair
• f67bda5 dynamic crosshair prefs: fix lower bounds
• bb14904 brusheditor: fix slider value box sizing issue
• 31ba28f brusheditor: fix base value slider [skip ci]
• 307e3b0 brushselectionwindow: use show_all when opening editor
• fab8a0b windows: fix msys2 dependencies
• f361e25 fix opening webbrowsers w. appimages [skip ci]
• fff4509 fixed typos
• f46b1e1 i18n: revert translation misunderstanding
• 105d7af Keymap Filter : Added the ability to filter keymaps. [skip ci]
• 539af1f Color Palette Bug : Fixed Palette editor gets confused with duplicate colors #922 [skip ci]
• f97feb3 Keyboard Input Bug Shortcuts don't work in non-latin keyboard layouts #974 : Fixed at least on my machine. [skip ci]
• 782a433 Merge accelmap-filtering feature
• bb4ea3a Merge fix for non-latin keyboard shortcuts
• b6c6eb7 i18n: change %d-formatted singular/plural to {}-format
• 9f600b7 Change $MINGW_INSTALLS to $MINGW_ARCH
• 5d51e9c Added "-s" to Makepkg-mingw
• 7a12693 Added Extra Options to Makepkg-mingw
• 66f2534 Added Intltool to Libmypaint Dependencies
• ea7b141 Update PKGBUILD
• 1e97b4e setup.py:
• 423950b setup.py: Ensure setuptools-compatible distutils are used
• 032a155 python: fix for Python 3.11
• 9795e3a Added webapp storyboard background
• bc6a950 BUILDING.md: Added dependency instructions for OpenSUSE
• 21cc7b6 ISSUE_TEMPLATE: removed in favour of new templates; .github: Initial commit for new templates
• d01ee7e .github: Added new templates
• 0af05de .github:feature.yaml: Added input for forum link
• 278c2ab .github:bug_report.yaml: Added link to community forums for user support
• c7ccf8d .github:qol.yaml: deleted
• b24bfcb CONTRIBUTING.md: Deleted; README.md: Removed references to CONTRIBUTING.md
• 0b720f8 Use standard cursor name
• d7d2496 Modernize cursor creation
• 5496b1c Catch error for non-standard cursor
• 9186d34 ci: Switch to GitHub actions