Merge AvatarThumbnail with Avatar.
Add user avatar api endpoint.
Tests.
Rogue Mock.
Test ThumbnailField field.
Missing url files.
Restrict incuna_mail due to change in kwargs.
More docstring details.
Return None if image is empty.
Fix docstring.
Update README and doc string.

[ci skip]
mock is not from the core libraries.
Merge pull request #35 from incuna/refactor-avatars

Refactor avatar views