Deforminator: Judgement day

Lots of bug fixes, and improved functionality

1. can select ROIs from any image, and redraw
2. can load saved node patterns
3. can select node patterns using keyboard shortcuts (1-9,0 = 1-10)
4. can save node patterns to the currently active save pattern slot
using ‘k’ keyboard shortcut
5. Keep button now assigns the current node pattern to the active save
pattern (displayed in edit box) instead of just adding one in somewhere
6. Reference pattern indicator
7. MUCH faster saves

Not yet implemented:
‘Reset reference pattern’ button: change the node pattern to which all
images are registered. This functionality only partially exists by
resetting the ROI (but that will bugger up previous node settings on
other images).