Key of hash _enumerized_values_for_validation handled unified as Symbol
Ooops. Key of hash _enumerized_values_for_validation handled
now really unified as Symbol
Tests added for polymorhic association.
Merge remote-tracking branch 'upstream/master' into activerecord-integration-bug
_enumerized_values_for_validation is using strings as keys now.
Merge pull request #159 from nagyt234/activerecord-integration-bug

Key of hash _enumerized_values_for_validation handled unified as Symbol