As a developer, my git repository may be large. The GitHub Org Folder plugin should only fetch the Jenkinsfile, not the whole git repository.

Currently, a git clone is done for every branch of every repository. For teams with a large code base (e.g. a .git directory of 1.7GiB (real example)) this can be bad:

1. It can take a very long time.
2. It uses a lot of disk space on the Jenkins server.

Instead, I propose we use the raw file download mechanism instead:

https://raw.<github-url>/<org>/<repo>/<branch-or-ref>/Jenkinsfile?token=<token>

We have all the parts needed for this. We can always fall back to git clone if the github server doesn't support the raw.<github-url> interface.