Update SolrResults.inc

Adam/Erin,

Responding to Adam's information about displaying temporal coverage dates and Mark Cooper's code suggestion, I've done the following:

Replaced 'concatted_date_mdt' =>, with 'pb_parent_coverage_Temporal_ms' =>, in usc:test-mezzanine array section. 
Removed 'concatted_date_mdt' =>, from usc:collectionCModel array section.

First time using GitHub so hopefully I'm doing this correctly.