In stack.sh, REGION_NAME is used to set environment variable
OS_REGION_NAME before using OpenStack client to configure accounts
for services. OpenStack client will try to find Keystone endpoint
in REGION_NAME to send the requests.
However, in the case of deploying multiple DevStack instances in
different regions with shared Keystone, Keystone is only running
in one the of region. When installing DevStack for the region that
does not host Keystone, OpenStack client will fail to find the
Keystone endpoint and thus DevStack fails to start.
This patch fixes this bug by introducing KEYSTONE_REGION_NAME for
user to specify which region Keystone is running in. Document of
multi-region setup is also updated.
Change-Id: I3e82c7ff69326d4171623299ffecea103d40c80d
Closes-Bug: #1540802
6f1781f968