Open sourcing tasks

[jstarks]

Tasks that we should consider completing before open sourcing:

• Add license/copyright information to repo and all files #561
• Reduce/eliminate unsafe code in the shims #560

[jaybosamiya-ms]

Closing as completed despite #560 not being closed yet, since we've successfully reduced the biggest contributor of unsafe in #592 to the point that I don't think it is a blocker to open-sourcing anymore. #560 will remain open to track further reduction of unsafe.