Add circle object to use for rotating objects
Fix missing scaling of bounding mesh in editor
Add circle for yaw rotation of selected object

Also restricted camera rotation to requiring CTRL to be pressed.
Changed control scheme to avoid ambiguities with shortcuts
Correctly apply relative rotations
Merge remote-tracking branch 'origin/master' into multiedit

Conflicts:
	ToolKit/Source/MainWindow.cpp
	ToolKit/Source/MainWindow.h