Fix env-generator doc formatting
Fix env-generator doc formatting

Bulleted lists must have whitespace before and after or they don't
render properly.

Change-Id: I7dcc58b8d9e02d99918bbdcc7d0fc3905d66f71c

openstack/tripleo-heat-templates,dprince/tripleo-heat-templates,openstack/tripleo-heat-templates,dprince/tripleo-heat-templates