Homophily inference

[Sepante]

Homophily inference function is added.
Initial tests are added.

[mannbach]

@lisette-espin We implemented these changes yesterday. Could you please briefly check if anything needs to be changed? Thanks!

[lisette-espin]

Hi @Sepante, thanks for the update, and sorry for the delay.

I checked the code. Everything looks good, but before we merge the new code, could you please clarify/add the following:

1. in graph.py

• please add the proper reference of your paper to the class docstring of the class (under "References")
• If your method assumes h_MM == h_mm please raise an exception if they are not the same.

2. For the tests, it would be great if:

• you set the random seed for reproducibility in all tests.
• remove the unnecessary comments.
• If your method assumes h_MM == h_mm please add that as validation too in the tests