PROV-561 Basic implementation of attribute for object representations
NOJIRA Add error checking
PROV-564 Basic implementation of interstitial media browser
NOJIRA Prevent fatal error when calling with incorrect params
Merge branch 'oops' into relationAttributes

Conflicts:
	app/lib/ca/BaseInterstitialController.php
Merge branch 'master' of https://github.com/collectiveaccess/providence into relationAttributes

Conflicts:
	app/lib/ca/BaseInterstitialController.php
Merge branch 'relationAttributes' of github.com:collectiveaccess/providence