Dynamic membership change

Dynamic membership change allows you to add or remove nodes from your cluster without cluster restart. You need to enable dynamicMembershipChange config option to use this feature.

Add new node:

• call _addNodeToCluster with new node argument on one of the existing nodes
• ensure that node was added - wait for callback or call _printStatus (except adding the second node. When switching from 1-node cluster to 2-node cluster you don't need to wait confirmation)
• launch new node with correct (new one) initial otherNodesAddrs

Remove node:

• stop node that you want to remove
• call _removeNodeFromCluster with node that you want to remove as argument, on one of the online nodes
• ensure that node was removed - wait for callback or call _printStatus

If you want to add or remove several nodes, you should do it one by one.