tool: Remove pointless __init__ methods

Some configurators had pointless __init__ methods. There is not need to
implement these if they are empty. Keeping them only cause developers to
copy and paste this useless code when they create new configurators.

Change-Id: I0885600fd8a2257d7d7a3ebe563bf6ee4ca9bb96
Signed-off-by: Nir Soffer <nsoffer@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/31740
Reviewed-by: mooli tayer <mtayer@redhat.com>
Reviewed-by: Francesco Romani <fromani@redhat.com>
Reviewed-by: Yaniv Bronhaim <ybronhei@redhat.com>
Reviewed-by: Dan Kenigsberg <danken@redhat.com>