Remove packaging script and files

This is in preparation for replacing the package script
with a new one, which makes use of fpm so that we can
get rid of minor details of debian and RPM packaging.
The new one will be more consistent with
python-neutron-plugin-midonet packaging script.

Change-Id: Ibe19eed568a3e0d97975688edd1f6318762b0b3e