Unfinished because untested. But, the script docker-updater is
tested and used.


This LXC requires a kernel >3.8 at least. (to be able to run docker in
LXC) It requires also "aufs" capabilities (apparmor.d permission, but
also available in kernel)

XXXvlab: we could run docker in LXC via a socket towards an host's
install of docker and remove this constraint.


It is meant to build image of applications based on a single git-sub
code.

It provides an IMAGE that does not requires 'git' tool, and won't
contain any git history.

Then, it'll be able to update this image by small "docker commits"
quite efficiently.


Currently the image produced can only be run on docker host that
support running aufs in the containers (this implies, that the docker
fs driver IS NOT aufs, that the host kernel support aufs, and that
permissions are set so that container can mount an aufs filesystem).