Merge pull request #75 from emanuelschuetze/master

Set version number to 1.3.1a
Changed Version to 1.4.dev
Droped support for python 2.5
Updated the url template tag
updated requirements.txt
fixed jsonfield for django 1.5
let travis manuell download django as long it is not on pypi
Let the user choose the language in his settings
fixed more url-template-tags
clean up the .gitignore
Update openslides/__init__.py
Merge pull request #77 from ostcar/django1.5

Changes for Django1.5
Merge pull request #78 from ostcar/master

There is not alpha0