Add new notify type that allows watching of new patch sets

Users can now watch the creation of new patch sets. They get notified
if a new patch set is uploaded, but also if a rebase is done from the
WebUI or the commit message is edited in the WebUI.

Change-Id: Ieabc4c00d2b185e5b452ac43706cb0fdd9d87f77
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
8 files changed