The octavia dashboard has a built-in barbican rest API client used
to access barbican for certificate selection during load blanancer
creation.
Unfortunately, this client used the "barbican" namespace, which is
now used by the barbican-ui dashboard.
This patch renames the octavia client namespace to be octavia-barbican
to eliminate any namespace collisions with the barbican-ui dashboard.
Change-Id: Idec2c182b2758a148ae9d0efa251510d5e7985a3