Honor --heat-user argument in heat launcher
Honor --heat-user argument in heat launcher

Previously, the --heat-user argument was not honored, and the "heat"
user was assumed. This patch corrects the issue so that the user
specified by --heat-user is used by the heat launcher.

Change-Id: I5b4a93f652272c781fc57373a483a9c2289dc248

openstack/python-tripleoclient