Updated openstack/openstack
Project: openstack/python-heatclient  884d5403bc647b13d17dbfc7f791ce451a3b4e6b
null
Pass empty dict not None for empty environment

The server rejects any request with a None environment, so pass an
empty dict not None (we should probably also make the server more
robust so it can cope with None, but this seems the quickest and
most backwards compatible fix for now)

Change-Id: I0c3e8cd14faf257528be2254070bc40821675431
Closes-Bug: #1273993