update german translation
Rename tab-add-to-group to tab-window-add-to-tabgroup and
tabgroup-add-to-group to tab-tabgroup-add-to-tabgroup
in tabs/tab.jl and wm/keymaps.jl.
You must update your keybindings for title and tabbar.

Add/improve text/doc strings in tabs/tab.jl and tabs/tabgroup.jl

Add defcustom marked-cursor-shape to commands/move-resize.jl
Use custom cursor if window marked to add as tab.

Improve text/doc strings in prg/compton.jl

Add missing text/doc strings in sawfish.
Update StyleTab/theme.jl text strings