update debian/watch

use updated debian/watch file taken from
http://anonscm.debian.org/viewvc/sepwatch/trunk/watchfiles/python-django-extensions_0.6%2Bgit201107051902-1.watch?revision=13&view=co
Imported Upstream version 1.2.0
Merge tag 'upstream/1.2.0'

Upstream version 1.2.0
New upstream version

* New upstream version
* use new debian/watch file
refresh debian/patches/01-werkzeug-package.diff