Add: github repo overview to the handbook

[lwasser]

This pr will close in part the open draft. because it's becoming large i'm breaking it up into digestable pieces.

This has an overview of our core github repositories. we could add examplePy in the future and pyospackage (i'll add that now actually)

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• To see the specific tasks where the Asana app for GitHub is being used, see below:
  • https://app.asana.com/0/0/1207456070199491

[kierisi]

done! added a couple of links and small grammatical changes.

[lwasser]

Thank you Jesse!! i'll go ahead and merge this as it's a smaller pr! we can always flesh it out more later as well!!