qtgr: Add enable flags for mouse interaction.

Enable flags for select, pan, zoom on mouse interaction.

Change-Id: Ic1f68048243d499a1c474669edbbdcd3ab758eec
Reviewed-on: https://iffwww.iff.kfa-juelich.de/review/119
Reviewed-by: Christian Felder <c.felder@fz-juelich.de>
Reviewed-by: Josef Heinen <j.heinen@fz-juelich.de>