Removed unused ActiveTriples predicates
Extract cleanup logic from spec_helper into ActiveFedora::Cleaner
Updates to Versionable

This brings versionable resources up-to-date with the latest Fedora4
code.
Merge pull request #519 from projecthydra/versions

Updates to Versionable
Merge pull request #517 from projecthydra/cleaner

Extract cleanup logic from spec_helper into ActiveFedora::Cleaner
Merge pull request #516 from projecthydra/remove_registered_predicates

Removed unused ActiveTriples predicates
Consolidate has_metadata and has_file_datastream into contains. Fixes #508