Updated ARTStor profile to fix dataProvider, spatial

Based on conversation w. Amy 4/29/2014.
The crosswalk is the authority (http://bit.ly/dpla-crosswalks)
Superceding earlier comment in ticket #6130, dataProvider should
_only_ come from dc:publisher (sourceResource.publisher).
The crosswalk says sourceResource.spatial is "n/a" for ARTStor.