Documentation: Change HTTP Signature Authentication recommendation

[cveilleux]

The current recommandation for implementing HTTP Signature Authentication, available here recommends the following module:

https://github.com/etoccalino/django-rest-framework-httpsignature
https://pypi.org/project/djangorestframework-httpsignature/

That module has not been updated in almost 3 years and contains a very broken rsa implementation.
See: etoccalino/django-rest-framework-httpsignature#13

You should update the recommandation for https://github.com/ahknight/drf-httpsig which is properly maintained and has an available pypi release named drf-httpsig

[tomchristie]

@cveilleux Would you be interested in making a pull request to the documentation, that we can then review?

[bozhodimitrov]

@cveilleux , @tomchristie Here we go :)