* refactors revocation of oauth2 tokens by adding revocation of access_tokens which will result in automatic removal on sso portal side
* drops unused return statement on same method
* adds assertions for correct revocation responses
* integrates authlib into project
* adds authlib package to requirements.txt
* refactors internal konova/utils/generators/generate_token method to use authlib's generate_token method and act as wrapper for backwards compatibility
* refactors OAuth views to be based on authlib's oauth client implementation
* refactors oauth model to work with authlib's oauth2 tokens
mpeltriaux