[MOD] Trigger event on new tracker item rating

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@47291 b456876b-0849-0410-b77d-98878d47e9d5
[ENH] Adding validation to the custom event rules

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@47292 b456876b-0849-0410-b77d-98878d47e9d5