=== How to deal with project branch reset ===
To some degree, the integration-gecko-projects repo should be self-healing. If the incoming changesets to a repo are incompatible (so an <code>hg pull</code> doesn't work), the script should blow away the source repo and reclone. The integration-gecko-projects target has will shortly have <code>force_push</code> set to True, so it should be pushing with <code>git push -f</code>.
However, project branch resets may become an issue; time will tell.