Implement Brande's Algorithm

[InterLinked1]

Brande's algorithm is the optimal algorithm for computing betweenness centrality on unweighted graphs.

Psuedocode on page 10 here: https://web.archive.org/web/20171013152036/http://algo.uni-konstanz.de/publications/b-fabc-01.pdf

Currently, this seems to be the only centrality algorithm missing from graphp's abilities.

[clue]

This feature makes perfect sense 👍

There are currently no immediate plans to build this from my end (no demand at the moment and more important outstanding issues currently), but I would be really happy to accept PRs 👍

(If you need this for a commercial project and if you want to help sponsor this feature, feel free to reach out and send me an email)

[ghost]

I would like to work on this issue.

[SimonFrings]

Hey @inkedtree, we're always happy about contributions, so feel free to file a pull request to implement this feature 👍

When creating a pull request, please make sure to also add additional tests to assure that your suggested changes work as expected.