added validations
tests blocked out; moved test into activefedora models
moved tests back out
made sort_title required
revised validations
implemented default comparator
fixed type validation
dates on save
Add dates before validation
after reworking
vocabs live with submodule
Added validations
Added timestamp concern. Closes pulibrary/pul-store#16
removed creator_contributor_validator.rb. not sure how it would up here
shortened 'provenance' to 'prov' throughout
was renamed
added comments and made order of attributes consistent
classes that use this need to provide a provMetadata stream; no longer defined here
toward pulibrary/pul-store#6
added characterization mixin; toward pulibrary/pul-store#3