network: Introduce the network package

This is the first patch of the topic branch that wants to end up with
the vdsm directory having all networking code properly sorted into
the network package and network scripts.

Change-Id: I532c179d4002ed1e8e5445d02297c8d5a6248647
Signed-off-by: Antoni S. Puimedon <asegurap@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/25908
Reviewed-by: Vinzenz Feenstra <vfeenstr@redhat.com>
Reviewed-by: Dan Kenigsberg <danken@redhat.com>
Tested-by: Dan Kenigsberg <danken@redhat.com>