Bump version to force tox to upgrade deps
Make email a required field in profile form
Rework how we tell if there is a profile class
Add support for a User model which extends AbstractUser

These are simpler as they are guaranteed to have an email field which
Oscar uses for authentication.
Add support for a truly custom User model

The new model must have an email field but Oscar will work without
anything else.
Remove usage of first_name/last_name from templates

Replace with get_full_name to better support User models that don't have
a first_name and last_name.
Add an abstract Oscar user model

This can be used by new Oscar installs.  It's the same as a the core
Django one but without a username.