Started to add support for using keyboard keys for binding buttons
combinations to tool application.
Known issues:
Can't combine with mouse buttons.
Focus issue if key pressed, then exit mouse (loses focus), and finally
release key - now on different focused component (commented).
Move mouse event is not bubbled upwards to production panel from
contained components.

Signed-off-by: Jakob Brandsborg Ehmsen <jakobehmsen.github@gmail.com>