Add module to decode HTML entities and to set ArtStor dataProvider

- Create decode_html module and add to ArtStor profile with
  prop=subject
- Create artstor_spatial_to_dataprovider moudle and add to ArtStor
  profile
Fix enrich-date module to handle wordy date ranges
Fix ARTstor provider
Fix for ARTstor dataProvider

- Update the artstor_cleanup module to work with the change in
  artstor_spatial_to_dataprovider
- Update the enrich-date module to null begin and end date fields
  when AD, BC. or AH in date value
Update ARTstor unit tests

- Remove copy_prop unit tests dealing with ARTstor dataProvider
- Fix enrich-date regex
retry wrapper updated (better output)
Merge branch 'develop' into internet_archive