Partial-Bug: #1378454
 -Feature: Send IPMI information of the cluster from server-manager
           to Cassandra database
 -Fix: Created ipmi.sandesh file to hold the structure to be sent.
       Modified viz.sandesh and vns.sandesh to have the sandesh structure
       elements.
  Made changes based on review-1
  Made changes based on review-2
Change-Id: I50cfb0104f2a8419395af76b68caf1785e4ae5ff
Merge "Partial-Bug: #1378454  -Feature: Send IPMI information of the cluster from server-manager            to Cassandra database  -Fix: Created ipmi.sandesh file to hold the structure to be sent.        Modified viz.sandesh and vns.sandesh to have the sandesh structure        elements.   Made changes based on review-1   Made changes based on review-2 Change-Id: I50cfb0104f2a8419395af76b68caf1785e4ae5ff"