Add SublimeLinter-Dashboard package

[philippotto]

Adds the SublimeLinter-Dashboard package which provides a dashboard like UI on top of SublimeLinter.

[philippotto]

@FichteFoll Do you know why the @packagecontrol-bot didn't kick in? All the other PRs seem to have gotten an automatic "accept" or "request changes" by the bot.

[FichteFoll]

No idea. All I can say is that the HTTP endpoint returns a 500 error code. I ran the checks locally, however, and here are the results:

Report for SublimeLinter-Dashboard

Repository checks

No failures

No warnings

Package checks

No failures

Reporting 6 warnings:

• The binding ['enter'] is also defined in default bindings but is masked with a 'context'
  File: Default.sublime-keymap
• The binding ['escape'] is also defined in default bindings but is masked with a 'context'
  File: Default.sublime-keymap
• It is not advised to specify mousemaps because of how limited the configuration options are. Instead, suggest the user to add specific bindings to their User package.
  File: Default.sublime-mousemap
• Command class 'SublimeLinterDashboardWrite' does not end with 'Command'
  File: SublimeLinter-Dashboard.py
  Line: 170, Column: 1
• Command class 'SublimeLinterDashboardOpen' does not end with 'Command'
  File: SublimeLinter-Dashboard.py
  Line: 237, Column: 1
• '.sublime-syntax' support has been added in build 3092 and there is no '.tmLanguage' fallback file
  File: dashboard.sublime-syntax

For more details on the report messages (for example how to resolve them), go to:
https://github.com/packagecontrol/py_package_reviewer/wiki

[FichteFoll]

@philippotto please address (or comment) the warnings about the mousemap file and the build requirement for installation.

[philippotto]

Sorry, I'll close this PR, because I don't need the package anymore as I found the LSP plugin to be a better fit for my needs.