Improve a little makefile

* Use sudo to run docker commands
* Build docker images once by using empty targets
* Autogen run once
* Added clean target
* Use long name for docker command arguments
* Include user foobar in the provision
Fixing build-dep by adding Zentyal source repo

* Fix smb conf and some minor helper for devel
Increase debug levels in smb config
Adapt readme to new docker containers
Enable sogo backend by default