Nudge function added. Testing nudge.
Nudge code working for nudge that is greater than or equal to leaf size.
Got rid of delete in nudge. Create is already destructive.
Add VoxelNudgeMode and preliminary UI grid for nudging.
Merge branch 'nudge'

Conflicts:
	interface/src/Menu.cpp
	libraries/voxels/src/VoxelTree.h
Switching nudge to cut/paste implementation. Preliminary.
Merge remote-tracking branch 'upstream/master'
UI for nudge completed!
Merge remote-tracking branch 'upstream/master'
Add nudgeVoxel shading in grid. Fix erase bug.
Remove magic numbers, fix spacing, and other code clean up in nudge code.
Merge pull request #916 from LionTurtle/master

Nudge