Fixing Hotkeys inconsistency for divecomputer/pref/numbering windows

Fixing the Hotkeys inconsistencies in subsurface, All the popups should
react to 'esc' and 'ctrl-w'/'cmd-w' as 'cancel'. also 'ctrl-q'/'cmd-q'
should quit subsurface.

Fixes #489

Signed-off-by: Gehad elrobey <gehadelrobey@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>