Drop MANIFEST.in - it's not needed with PBR
Drop MANIFEST.in - it's not needed with PBR

setup.py use pbr, so we no longer need MANIFEST.in.

Change-Id: I7de6e4fdea10a6aa89020e70338f5bc31156a5d9

openstack/murano-agent,openstack/murano-agent,openstack/murano-agent,openstack/murano-agent