Add support to replace cluster node with another node

Add a new cluster action which is CLUSTER_REP_NODES.
-- This action will replace the nodes of the cluster with the nodes do not belong to any clusters and have the same type of PROFILE

-- The sample request params like this:
      {
          "rep_nodes": {
          "node1": "rep_node1",
          "node2": "rep_node2"
          }
      }

-- API will check and validate the request parameters, After that, request will be sent to ENGINE

-- ENGINE will load all these nodes and then check:
    1. Nodes exit or not
    2. Nodes' status check
    3. Profile type match or not
    4. candidate nodes belong to a cluster or not

-- Create a CLUSTER_REP_NODES action to process the request, and a number of NODES_REP actions will be created to process each node

Some more ideas:
1. support deletion-policy or not