As a Gluster admin, I want to be able to know which bricks are arbiter bricks. Note: Just looking at volume type does not tell me if a volume is a distributed-replicat using the arbiter feature or not.

# gluster volume info
Volume Name: testvol
Type: Distributed-Replicate
Volume ID: ae6c4162-38c2-4368-ae5d-6bad141a4119
Status: Created
Number of Bricks: 2 x (2 + 1) = 6
Transport-type: tcp
Bricks:
Brick1: server1:/bricks/brick
Brick2: server2:/bricks/brick
Brick3: server3:/bricks/brick (arbiter)
Brick4: server4:/bricks/brick
Brick5: server5:/bricks/brick
Brick6: server6:/bricks/brick (arbiter)
Options Reconfigured :
transport.address-family: inet
performance.readdir-ahead: on
@nthomas-redhat @Tendrl/qe @shirshendu @shtripat @GowthamShanmugam @anmolsachan