Schedule post-trip docsprint

[dcwalk]

Copied from @titaniumbones in https://github.com/code-at-the-edge/curriculum-materials/issues/53:

Would be cool to do a post-trip sprint of some kind? We need docs for various audiences:

• ourselves (!)
• possible collaborators who might be interested in contributing to/critiquing our work on GH (local & remote)
• on-the-ground teachers in the contexts we visit (for now at least this means KGBV)
• students themselves