[Feature] developer circle chart

[tyn1998]

Description

@tieway59 finds GitHub Social Circle(see this discussion), which presents us with a great way to demonstrate developer network in GitHub.

And I come up with an idea that we can implement this kind of chart and make it available on the repo root page, as illustrated below:

Welcome any further discussion!

[TieWay59]

@tyn1998 you can also ship this chart in a more straightforward & condensed way.

[2000wyt]

If using a chart similar to GitHub Social Circle to demonstrate developer network, set the size of the contributor's avatar according to the contributor's contribution to this project, and arrange the contributor's avatar in a beautiful form. Compared to before, people can identify active contributors in an intuitive and quick way.