Beta testing for v0.8.0

Please test this release using this issue as starting point / testing ideas: #884

Release Notes:

Features

• The config file location changed to ~/.config/flameshot
• Fix capture after pressing ctrl + S during textarea input (#311)
• Add translation:
  • Japanese (#361)
  • Brazilian Portuguese (#364)
  • Serbian (#376)
  • Dutch (#440)
  • Ukrainian (#464)
  • German (#467)
  • Slovak (#525)
• Allow enter key to copy image to clipboard (#362)
• side panel: Add thickness slider (#374)
• Add support for saving as JPG and BMP files. (#436)
• Allow 45 degree adjustment for some tools (#439)
• Add option to close after capture
• Add a basic launcher panel.
• Add option to auto copy URL after upload (#553)
• Add a circle counter tool.
• Replace the blur tool with pixelate tool.
• Convert buildsystem from QMake to CMake.
• Add launcher action into .desktop file.
• Option to save to file when copied to clipboard.
• Button added for sidebar menu
• Improved Windows support
• Windows Installer
• Flatpak, appimage, snap support

Fixes

• Exit non-zero when aborting with --raw. (#424)
• Enable Pin and Text tool by default. (#443)
• Fix the problem that moving or resizing does not affect screenshot. (#459)
• Fix problem with re-enabling disabled tray icon (#495)
• Fix compilation problem against Qt 5.15.