update fixity responses to use PREMIS vocabularies and hash-uri subjects
Use info:fedora/ as the default resource namespace
Killed off legacy (Atom) JMS format

Resolves: https://www.pivotaltracker.com/story/show/62246234
Merge pull request #202 from futures/fixity-uris

Fixes https://www.pivotaltracker.com/story/show/62243562
adds access roles API to fcrepo-webapp REST API
adds access roles UI to node pages
adds an RDF pointer to the access roles endpoint
fixes camel case fcr:accessRoles endpoint, making it fcr:accessroles
made enum fields private
removed unneeded roles provider from AccessRolesResources