Add error_code to error response messages

Signed-off-by: Simon Luijk <simon@simonluijk.com>
Allow SocialAuthSerializer to swapped

Signed-off-by: Simon Luijk <simon@simonluijk.com>
Return error response if not user associated.

Signed-off-by: Simon Luijk <simon@simonluijk.com>
Add UniqueEmailUserSerializerMixin

Signed-off-by: Simon Luijk <simon@simonluijk.com>
Add PasswordSerializerMixin

Signed-off-by: Simon Luijk <simon@simonluijk.com>