Working on rotating images.
So far only 90 degree rotation is supported.
Only the image is currently being rotated.
Overlays, debugger, and the navigator still need to be updated to support rotation.
Rotating overlays.
Fixes made after first code review of rotation.
Revisions to rotate after second code review.
More rotation documentation.
Merge pull request #185 from robhobbes/master

Adding partial support for rotation.