Insert the "root_znode" path before "master_redis_node_manager_lock" and expose via accessor

We were having issues while attempting to use the node-manager across two clusters. The first cluster would start up, properly pick master and correctly handle failover however for the second cluster a master would never be promoted and though failover seemed to work the cluster status was not being properly tracked by node-manager.

This fix has been applied to our staging environment and appears to be doing the right thing (now). In attempting to test this I found that there was going to be a lot involved and wanted to get feedback on what would make sense to test, at this point, if anything.