Devstack: Add admin creds in magnum.conf
Devstack: Add admin creds in magnum.conf

This patch adds admin creds in magnum.conf, admin creds are used for periodic
task job to query bay status from heat service.

Partial-Implements: blueprint add-periodic-task
Change-Id: I11b8823ef7003bb850b74148f847d65dfabd335f

mjbrewer/testindex,paulczar/magnum,LaynePeng/magnum,Alzon/SUR,sajuptpm/magnum,Tennyson53/SUR,LaynePeng/magnum,eshijia/SUR,ffantast/magnum,dimtruck/magnum,hongbin/magnum,ChengTiesheng/magnum,openstack/magnum,annegentle/magnum,ddepaoli3/magnum,ramielrowe/magnum,eshijia/SUR,dimtruck/magnum,ChengTiesheng/magnum,mjbrewer/testindex,eshijia/magnum,eshijia/magnum,ramielrowe/magnum,hongbin/magnum,Tennyson53/magnum,ArchiFleKs/magnum,mjbrewer/testindex,Tennyson53/SUR,ffantast/magnum,jay-lau/magnum,ddepaoli3/magnum,sajuptpm/magnum,ArchiFleKs/magnum,Alzon/SUR,Tennyson53/magnum,paulczar/magnum,openstack/magnum,annegentle/magnum