Updates for 3.1
-declare allowed_actions on ItemRequest
-ItemEditForm() method public for consistency
-has_extension called updated for 3.1 compatibility
-canPreview based on record class's implementation rather than CMSPreviewable implementation
-Preview button addition withheld if Link method has not been defined or returns null
Remove linking for action messages, wrap all item titles in quotes
Merge pull request #5 from clyonsEIS/master

Merged Updates for 3.1 from clyonsEIS