DS-4024: Discovery ignore indexes

Discovery is supposed to be ignoring the "dc.description.provenance" field, based on this Spring configuration:
https://github.com/DSpace/DSpace/blob/master/dspace/config/spring/api/discovery.xml#L84

However, if you search in any DSpace 4.x instance for a Submitter's email address or name, you will get a results listing of everything that submitter has deposited within DSpace. We are seeing this in *every* DSpaceDIrect instance (all running on 4.x).

It's also can be replicated in the Demo site (both XMLUI and JSPUI), for example:

JSPUI search for "dspacedemo+admin@gmail.com": http://demo.dspace.org/jspui/simple-search?query=dspacedemo%2Badmin%40gmail.com

You can similarly search for "dspacedemo+admin@gmail.com" in XMLUI to get results which show all Items deposited by that user. The ONLY metadata field with that information is the "dc.description.provenance" field. 
New way of implementing ignored indexes. Incomplete?