CSPACE-5887: Allow event listener to 'null out' computedCurrentLocation value in Cataloging / CollectionObject if that value is blank / null in most recent related Movement record.
Merge pull request #90 from aronr/CSPACE-5887

CSPACE-5887: Allow event listener to 'null out' computedCurrentLocation ...
CSPACE-5887: Minor cleanup of event listener to mirror work done in PAHMA-738: only 'null out' non-blank existing computedCurrentLocation values when the most recent Movement's currentLocation value is blank.
CSPACE-5887: Update event listener with updated logic also used in PAHMA-734.