[MOD] Add support for translation-related notifications

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@49630 b456876b-0849-0410-b77d-98878d47e9d5
[ENH] Allow watching page changes individually rather than only any activity

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@49631 b456876b-0849-0410-b77d-98878d47e9d5
[MOD] Exclude current user from notifications

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@49632 b456876b-0849-0410-b77d-98878d47e9d5