fix #237 - enable shortcuts to move tabs around
tl;dr Enable CTRLSHIFTPgUp/PgDown shortcut to move tabs left/right
- only grabbed when using multiple tabs
- consistent with existing CTRLPgUp/PgDown shortcuts
- consistent with default Terminal behaviornable
- default in libadwaita tabs
details (also see #237 (closed)):
- libadwaita propagates them to the terminal when there is only a single page/tab
- with multiple pages/tabs, shortcuts get handled to select/reorder tabs as in other gnome apps
- same behavior as default Gnome Terminal
- this seems a reasonable trade-off for the few case where TUIs might want to use those shortcuts
- leave CTRLHOME/END disabled for now as those shortcuts are partly covered by Alt+0-9 or Ctrl+PgUp/PgDown and also more prominently used by vi
- see also #118 (closed) and #155 (closed)
Edited by Martin Nowak