Support Aardvark metadata schema

[thatbudakguy]

The field names & schema in the layer model (and potentially elsewhere) are out of date:

geo_monitor/app/models/geo_monitor/layer.rb

Lines 17 to 22 in b4cad62

	layer.institution = schema['dct_provenance_s']
	layer.rights = schema['dc_rights_s']
	layer.layername = schema['layer_id_s']
	layer.bbox = schema['solr_geom']
	layer.url = references['http://www.opengis.net/def/serviceType/ogc/wms'] || references['http://iiif.io/api/image']
	layer.active = true

We need to use the Aardvark schema here in order to be compatible with modern version of geoblacklight.