Merge pull request #8 from GSA/Release-1.23

Release 1.23 - Schema 1.1 Updates
Merge pull request #9 from GSA/Release-1.23

replacing parent_id with parent_unique_id for isPartOf
license fix
Merge pull request #10 from GSA/license-fix

license field fix
validation
adding ISO 8601 options
dont strip if Null
fields fixed
fixes #138 trailing spaces
avoid empty values in resource
mega validation
schema 1.1 regex updates by Phil, closes #159
speedup