Added conditional to catch of unindexDocuments method designed to handle and...

Added conditional to catch of unindexDocuments method designed to handle and fix the case where a facility is deleted from a network but the reference to the facility would remain in the network. Issue was the readDocument method was throwing GitFileNotFoundException which was to be expected given the deletion of the facility, however the code on an exception would return false and therefore not do the delete in sparql necessary to remove the facility, and it's reference to the network. Added unit tests to cover new case

Closes EMC-268