Release 1.1.0

This is the first release in the new unstable 1.1.x series, leading up to 1.2
which is expected around the end of the year.

Changes in this version:

• New command flatpak kill to kill running flatpak instances.
• The remote argument is now optional in the flatpak install in
  interactive installs. Instead you are prompted for which
  remote to install from.
• All commands printing tables now support --columns option to specify
  exactly what to output.
• flatpak uninstall now supports --delete-data to delete the application
  data directory in your homedirectory. If no application is specified
  it will remove data from all uninstalled apps.
• flatpak list now supports filtering by runtime with:
  --app-runtime=org.gnome.Platform//3.24
• flatpak remote-ls can now show the runtime used for each app.
• flatpak repo now supports --info to show information
  about a repository, and it is the default operation
  for the flatpak repo.
• flatpak repo now supports --commits to list commits in branch.
• flatpak now logs transactions to the systemd journal if built
  against libsystemd.
• libflatpak now exposed FlatpakInstance for a running instance.
• Better error output if a flatpak command is misspelled
• Drop support for migration from xdg-app (previous name for flatpak).
• New library function flatpak_installation_get_min_free_space_bytes.
• In interactive mode "yes" is now the default in most prompts.
• Bumped ostree requirement to 2018.9
• Cleanups and improvements to the test suite.
• Improvements to documentation.
• buildsystem support for coverage generation.

$ sha256sum flatpak-1.1.0.tar.xz 
576ca12484171dd57fd2ca45c5583e4a94b1b24a0fc0b6d1695eaa9908e4722e  flatpak-1.1.0.tar.xz