How do I migrate the complete RTC change set history of a stream to a git repo?

We are currently using RTC 4.0.7. We have a project that is about to be open-sourced, and the open-source project will be maintained in a git repo. We need a way to preserve file histories when the code is migrated. Is there a tool or API that lets me check out individual change sets from the history of a stream, so that I can deliver them somewhere else?

Does RTC 5 support moving change sets from a RTC stream to a git branch?