Updated requirements file for running nosetests

[dhiraka]

I was trying to update python-saml from 2.1.3 to 2.1.6
I had to install the following dependencies in that process. This is the updated requirements file.
However, I was stuck at one point. In python-social-auth/social/backends/azuread.py we have:
from jwt import DecodeError, ExpiredSignature, decode as jwt_decode
There are no such errors or exceptions defined in jwt.
I am stuck here.
I could be missing something here. I couldnt find such issues anywhere else.

[omab]

Closing since this pulls in too many dependencies (probably from your own project requirements).

Thanks!