Modifications to debian/-Files for python policy
The following patch applies a few guidelines described in the Debian Python Policy at http://www.debian.org/doc/packaging-manuals/python-policy/index.html
1.) Replaces versioned dependencies python2.4-something with generic python-something
2.) Removed the superflous python2.4 dependency (added automatically by ${python:Depends})
2.) Replaced XS-Python-Version: 2.4 with >= 2.4, gajim should run on python 2.5 just fine