Buildrone Virtual Machines

[raevol]

Builddrone might be extended to start up a vm (kvm/qemu) to do builds, this vm should be very well isolated and startup in a clean state. With that we have the opportunity to build, check and package on other distros as debian and also to use builddrone on untrusted code like the mob repository. This might be helpful to do a first automatic filtering of contributuions if something merges, builds and passes the testsuite.