Add Github integration to automatically create private repos based on a template

[vladolaru]

When a new hosting solution is purchased, a new WordPress site needs to be created on our infrastructure managed by PD Deck. A PD site needs to clone some Github repo that follows the structure of our wpsite-starter repo.

We need to integrate a Github API wrapper (probably this one https://github.com/KnpLabs/php-github-api as it seems well maintained) to create a new private repo in the Pressody organization and have the wpsite-starter repo function as a temple for it.

Once we have the new Github repo URL, we can pass it to PD Deck to do its thing.