Add expiration to API token

[ycrumeyrolle]

Currently the API authorization is granted through an API key which has unlimited lifetime. As there is no policy, token renewal cannot be enforced. It would be more secure to have a short life token instead, or a fixed-time living API key.

Can you consider to integrate this feature? https://pypi.org/project/django-rest-knox/ seems to be a viable solution for that.