New fields: Image.height, Image.width, Annotation.rotation.
Attempt at finding the actual dimensions of the crop out from the the full size image but iipimage server is not reliable enough.
Added migration for new fields
Merge branch 'master' of github.com:kcl-ddh/digipal
Startedthe prototype for the rotation of the annotations.
Rotation. Added JS lib.
Merge branch 'master' of github.com:kcl-ddh/digipal