ndb/src/mgmclient/CommandInterpreter.cpp:
  Adding the judgement for node type to distinguish the data nodes and non-data nodes.
  From the return value. Management client can't distinguish the really not connected
  status for data nodes and status of non-data nodes.
  We can get the connect status about non-data nodes from version, if the version is 0, 
  it means no connected status.