Spike: Collect and document GH metrics for measuring Operate First community

[hemajv]

Document all available (Augur) and relevant GitHub metrics we would like to have for measuring the Operate First community.
cc @cdolfi @xtuchyna

[hemajv]

Initial doc created here: https://docs.google.com/document/d/1Yocr6fk0J8EsVZnJwoIl3kRQaI94tI-XHe7VSMFT0yM/edit?usp=sharing

[hemajv]

@durandom created a document to start collecting some ideas around metrics we would like to have: https://docs.google.com/document/d/12JjCKzYzRBihR1cn6L0htp1yHQqZzKDEiQZCO7uz7qw/edit?usp=sharing

[hemajv]

Initial exploratory notebook with visualizations for some of the metrics can be found here: https://github.com/operate-first/community/blob/main/metrics/community_metrics.ipynb