Make --profile load from environment variables
Make --profile load from environment variables

--profile argument can be loaded from OS_PROFILE environment variables
to avoid repeating --profile in client commands.

Co-Authored-By: Hieu LE <8ad7c52ea0909d841e9aacbd3c71505f59ffb142@vn.fujitsu.com>
Change-Id: Ia24144f5858d05566ffa32a329884dc4dd7ec570

openstack/python-mistralclient,openstack/python-mistralclient,StackStorm/python-mistralclient,StackStorm/python-mistralclient