Develop Github workflow documentation for the wiki

[lucypatterson]

Suggested text:
https://docs.google.com/document/d/128RODa0Qz_--bckpuiZREVIbe17NxjBXpdUsThYzKkY/edit#
@nosy79 @gitstief - please check and comment. Thanks!

[nosy79]

@lucypatterson:
Probably we need 2 documents: one is yours, which describes a lot of the work flow and one would be a more technical document that I put into the wiki - it will be quite short.
When should this be ready?

[lucypatterson]

Let's try to get it done this week. It's been hanging around as an issue (albeit not documented in github) for a while now. I'll also work on issue #106.