Run on all user repositories

[cmdoret]

In the context of SDSC Internal Knowledge graph, it would be useful to let gimie run automatically on all repositories associated with a user. We could add that feature in gimie itself.

Objective: Allow to easily retrieve graph of all repositories for a given user.

Requirements:

• gimie user <username> works
• Feature available from Python API
• Can run on either repositories "owned" by user, or where user has "contributed" (i.e. has commits in the codebase).