Fix neutron-nova notifications

Fix neutron-nova notifications

In our neutron.conf we configure both keystone v2 and v3 options,
which confuses the keystoneclient code responsible for deciding
which to use.  For whatever reason, having it talk to the
unversioned keystone endpoint and letting the client decide which
version that way makes it happy.  Except that we write a wrong
value for project_name, which makes it unhappy again.

This change fixes both of those issues, which allows notifications
to work again.

Change-Id: Ic3a329354d0ed071363183b5e06c0a42d2dd84ad
Closes-Bug: 1519525