Upgrade to django-allauth for authentication
Override login templates in core.
Update settings and title.
Remove registration templates.
Merge branch 'allauth' into merge-py3-django16

Conflicts:
	pip_requirements.txt
	readthedocs/templates/core/header.html
	readthedocs/templates/core/home-header.html
	readthedocs/templates/registration/activate.html
	readthedocs/templates/registration/activation_complete.html
	readthedocs/templates/registration/activation_email.txt
	readthedocs/templates/registration/logout.html
	readthedocs/templates/registration/password_reset_email.html
	readthedocs/templates/registration/registration_closed.html
	readthedocs/urls.py
Initial porting for switch to py3

Mostly done with 2to3, some additional cleanup as well
Bump package releases/changesets for py3/django support

Bumps releases/changesets for:
* django -> 1.6.5
* south
* slumber -> git PR for py3 support
* django-nose
* django-redis
* django-haystack
* django-tastypie
* django-profiles
* gunicorn
* django-redis-cache
* launchpadlib (though it still doesn't support py3)