misc...
* fix: update projections on prev/nextleakspot
* use active projection for prev/nextleakspot tracking
* fix of: no redo available after ( nothing selected + M1 click ) in 2D
* fix: nudge left, right, up, down commands work in scale, rotate, clipper manipulator modes
* deprecated 'Disable system menu on popup windows' preference, was doing nothing
* preference: Nudge selected after duplication (def = no)
* preference: Left mouse click tunnel selector (def = yes)
