More build info

Added commits id for source dependencies (oq-nrmllib, oq-hazardlib and oq-risklib) in the packager log.
Saved all ssh commands sent to LXC machines used for tests in devtest.history and  pkgtest.history files to be able to reproduce manually what happens during automatic tests (LXC sshd configuration file is changed to add a command wrapper be able to do it).