webadmin : Volume and Brick Capacity UI

This patch provides column for displaying the capacities of
volumes in the Volumes table before the volume activity
column of Volumes tab.And Brick capacities in Bricks
sub-tab of selected volume.

Change-Id: I04151d78838c1398cff42c84104e21d61d9c7747
Signed-off-by: Anmol Babu <anbabu@redhat.com>