Add keyboard shortcuts inhibitor

This adds a new protocol to let Wayland clients specify that they want
all keyboard events to be sent to the client, regardless of the
compositor own shortcuts.

This protocol can be used for virtual machine and remote connection
viewers which require to pass all keyboard shortcuts to the hosted or
remote system instead of being caught up by the compositor locally.

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Jonas Ådahl <jadahl@gmail.com>
3 files changed