Turn on l3 agent and external network bridge for Brocade plugin

Fixes bug: 1186467

Change-Id: I534a6f415ab14b2f4d75f244bbe79582ae2046bb
Use service role instead of admin role for service users

Instead of using a full admin role to validate tokens just use the
service role. Change where possible, some services use the service user
for more then just token validation.

Fixes bug 1153789

Change-Id: I0801475b62a7b025fdd871f52d8606aa614d1a32
Merge "Turn on l3 agent and external network bridge for Brocade plugin"
Merge "Use service role instead of admin role for service users"