Require a minimum of Django 1.4.

* Require a minimum of Django 1.4.5
* Run Travis tests with 1.4.5 and 1.5.1
* Drop Django's timezoned now fallback for 1.3
* Drop override_settings fallback
* Updated requirements in README
Small PEP8 indentation issues.

Fixups in setup.py and web tests.

Django 1.4 support in README.
Python 2.5 patch has arrived in django-setuptest.
Integration of django-webtest support.

Intelligent 'browser-like' parsing and form behaviour.

See: http://webtest.pythonpaste.org/en/latest/index.html
Updated Dutch translations.
Bump version to 0.4.1
XFrame exempt for newsletter preview.
Revert "Python 2.5 patch has arrived in django-setuptest."

This reverts commit 04547ea775698af57aa48e972931cee5ab5c3b9a.
Drop official Python 2.5 support.
1.5 tests should pass now.
Updated contributors.
Updated and restructured changelog.
Added changes to setup.py README