divide repo #72
Description
Let's divide the repo in a fashion similar to tc-admin / community-tc-config. We can provide a "skeleton" repo, maybe taskcluster/monopacker-base, with some useful and documented (#71) var files and scripts which each deployment can fork and adapt. Then we can fork that ourselves to mozilla/community-tc-monopacker, and firefox-ci can for it to mozilla-releng/firefox-ci-monopacker.