Sanic-security

+ Authorization revamp. `Permission` object removed as permissions are stored in a `Role` object. An account's roles can be accessed via the `roles` variable value via a many-to-many relationship.
+ Session access/refresh token's.
+ Model revisions.
+ Improved registration error handling.
+ Password character limit check during registration.
+ Uid removed.
+ Test improvements.
+ Documentation revisions.

+ Setup.py optional development dependencies.

+ Edge case scenario where session expiration is disabled but client session expiration is true has been mitigated.

+ Sessions can now be configured to never expire.
+ Documentation revisions.

+ `DATABASE_URL` configuration variable added.
+ Test server database initialization url now uses the `DATABASE_URL` configuration variable instead of a hardcoded url.
+ Improved imports.
+ Improved configuration documentation.

+ Environment variables can now be loaded into the config.
+ Login can now work with an email or a username. This can be enabled by setting `ALLOW_LOGIN_WITH_USERNAME` true in the config.