Editor: Functionality for Double-Clicking in Tables
Double-Clicking an object in the tables should trigger the "Edit Record" action.
Note: Region-Map Double-Clicking should also trigger the "Edit Record" action on the cell clicked on (which isn't available in the right-click menu).
Also, notice that the "Edit Record" action of a Reference is for that specific Reference, not for the Reference-able it's based on.
(RM-1918 from redmine: created on 2014-09-15 by Paul McElroy, , closed on 2014-10-27 by Marc Zinnschlag, relates #504 (closed))