Add session specific per user, not global like it's now about ci

[KrauseFx]

Alright, quick update on the git pull and git push using the user's session. A few things:

We currently have:

• GitConfigDataSource, which is a data source for configuration files, meaning list of projects, and CI config
• GitHubSource, the connection to GitHub, GitHub specific, used to report build status, list repos, etc.

We need a new class that does the git overhead, around auth, error handling, managing of repos, etc. What I was thinking, having a GitHelper class, that does it. As part of each method call, we require the user of the class to pass a valid GitHub session. The class also verifies that we only work with https:// URLs just to unify the whole thing.

The user of the method call can decide:

• Was it a user action? If yes, they're gonna pass the user's auth token, so their face is gonna appear (e.g. https://github.com/KrauseFx/ci-config/commit/d5db054433552b1a82cfed8c913d67d6d6e320b8)
• Was it not triggered by being on the CI front-end by a user? (e.g. scheduled job, triggered by a commit, triggered by time)? We're gonna need a fastlane.ci user, so that not a user session is being used.

I started looking into how git auth works for temporary pulls and pushes, and it seems like there is no good built-in way to contain the whole thing. Will consult with some of my friends who know more about git.

It's tricky to pass the credentials, without affecting the whole system, and not leaking the data anywhere (build output, error case, etc.)

Open TODOs

• The things above
• When and how do we authenticate the CI itself for the second kind of git commits? Where and how do we store the login?

[KrauseFx]

Moved to #33