4.20.6

- Add xfw_screen_get_monitor_for_gdk_monitor()
- Add missing "New in 4.20.6" docs section
- Add missing chain up to parent class
- I18n: Update po/LINGUAS list
- XfwMonitor: Fix (xdg_)output_done event handling
- XfwMonitor: Fix typo and initialize class member
- Ignore workarea/workspace count mismatches
- Fix incorrect max to clamp workspace number to
- Implement workspace geometry for wayland
- Add XfwWorkspace:geometry property
- Fix missing workspace signal connections in test program
- Add test program to enumerate workspaces
- Fix X11 workspace geometry and layout getting out of date
- Fix incorrect col & row ordering for Wayland workspace coordinates
- Fix width -> height typo for XfwWorkspaceX11 geometry
- Add fallback monitor on X11 if XRandR doesn't report anything
- Don't depend on wayland-scanner and wayland-protocols
- XfwWindowWayland: Connect to XfwScreen::monitor-added
- XfwWindowWayland: Connect to XfwScreen::monitor-removed
- Translation Updates:
  Georgian, Kazakh, Korean, Lao, Russian, Turkish