[Settings][Spices] Fix IO error
Prevent flashing previously viewed detail, bind to preview window destroy/delete to prevent actual destruction of window, correct progress bar text for subsequent screenshot downloads
Use gi.repository version of Pango, causes strange errors with some
other libraries.
Merge pull request #1713 from mtwebster/pango-import

Use gi.repository version of Pango, causes strange errors with some other libraries
Merge pull request #1711 from rjanja/ai-fixes

[Settings][Spices] Minor fixes to applet installer
Merge pull request #1710 from dalcde/settings-fix

[Settings][Spices] Fix IO error
Merge remote-tracking branch 'upstream/master'
[Window Manager] Handle workspace-shift hotkeys on key-release instead of on key-press.

This makes it possible to support multiple rows of workspaces, by
differentiating between short and prolonged key presses:
a short press of Ctrl+Alt+Up or Ctrl+Alt+ Down opens Expo or Scale,
whereas a prolonged key press shifts workspace-up or down.
[Rows of workspaces] Implement a configurable number of workspaces.

This requires a fixed version of Muffin to work, otherwise shifting
up and down between rows will not work.