[libvirt] Reworked patch set to add UID/GID support for containers

Combined all UID/GID patches, taken into account Dan Berrange feedback. Now UID will be based off the current UID. Sandbox Shell is no longer used when using LXC containers. Connect will now just execute a shell within the container. [sandbox PATCH 1/6] Add UID/GID support for use with interactive [sandbox PATCH 2/6] We should not turn on the sanbox shell by [sandbox PATCH 3/6] Only create the destination directory if it does