Complete rewrite to use class-based views, with full Django 1.5 support.

--HG--
branch : django15
Merge Django 1.5 compatibilty branch into default.
Update INSTALL and README for new version requirements.
Move import of Django's get_version into django-registration's get_version, to avoid dependency-order problems.
Fix version number reporting so we can be installed before Django.
Clean up a test failure.
Some final pre-release cleanup.
Added tag v1.0 for changeset c5f81c8e59e8
Removed tag v1.0
Let's try that again.
And with correct docs URL.
Added tag v1.0 for changeset 602c6c52b135
Removed tag v1.0
One final tweak.
Added tag v1.0 for changeset aafb10048c77