Fixes for creator field for MWDL.

* Added supression of "creator" field if the value is "creator".
* Created module for cleaning creator field for mwdl.
Do not shred dataProvider on semicolons for MDL

- Remove shredding on semicolons for publisher in the MDL profile
  since the publisher field is copied to dataProvider
Map only contributor to dataProvider for DLG

- Update DLG profile to unset the dataProvider field then create
  it and copy the contributor value to it
Created module for cleaning creator field for mwdl.
Added supression of "creator" field if the value is "creator".
Merge branch 'szymon_workbranch' of github.com:dpla/ingestion into szymon_workbranch