use persisted method instead of pid.
Accessor got lost in merge.
Mods datastream and test to help with parsing of Aleph->Mods data.

add authors accessor.

add accessor for primary name, change datastream logic slightly.
methods to retrieve or create a person object based on a string value

Conflicts:
	spec/models/person_spec.rb
Convenience methods to convert Aleph data
Add author data to work
better handling of no results.
Merge pull request #6 from Det-Kongelige-Bibliotek/final_author_fix

Final author fix