added image utils for convert tiff to jp2.
added re-generate access and thumbnail images for a work.
change to request img regen via ajax, and updated to get job from parentwork id if no job found for the current work.
merged in latest changes.
minor update.
Merge remote-tracking branch 'origin/master' into dsc-305
minor update.
refactor reprocess methods into reprocess controller and service.
updated to schedule a regen img job.
Merge pull request #513 from nla/dsc-305

Dsc 305