Profile urls seem wrong.

The [profile and list](https://github.com/incuna/django-user-management/blob/master/user_management/api/urls/profile.py#L15) (other profiles) and my profile seem to be mixed up in a way that looks very confusing.

I will make `api/urls/profile.py` only deal with the logged in users profile and add a new `api/urls/users.py` to deal with other peoples profiles.