"improved droppedImage() mechanism" - catching up with Jens' commit https://github.com/jmoenig/morphic.js/commit/ec2df19cf292593ccb2aae3a471d531200e1fedb
mouseEnterDragging fix - catching up with Jens' commit https://github.com/jmoenig/morphic.js/commit/3ffb650969c6130b7c0a2f34881676ef2b87c803
rebuild and docs