Base updates to datastream, models, and views for images
for new image metadata requirements.

Edits needed to pass db:migrate
Modifies spec test to use new fields and remove old fields.
Adds labels, hints, and defaults to image views.
Cleans up spec test for new image metadata fields
Merge pull request #8 from uclibs/images/#53

Updates to datastream, models, and views for new image metadata requirements.