"Allow/enable multiple documents to be selected when attempting to link documents"
Updated. Added required upgrade item to upgrades table.

Committed by: Kevin Fourie
Reviewed by: Conrad Vermeulen

git-svn-id: https://kt-dms.svn.sourceforge.net/svnroot/kt-dms/trunk@7853 c91229c3-7414-0410-bfa2-8a42b809f60b