GitLab

* New packages format lets you select source control system in use
* Packages file now includes root repo explicitly
* Scripts darcs-all and push-all updated for the new packages format only
* New sync-all script, intended for use after Git changeover and for buildbots right now
* Had to remove libraries/bootstrapping from tree since Git cannot track empty directories without a hack
* Determine checkout date with Git using Darcs fallback in aclocal.m4

OK, so the name is a bit wrong now...