Change process management of DTM to improve HA behavior

Current process management model for process type DTM enforces and soft node down behavior which kills all processes in a node where a DTM process terminates abnormally. The DTM process is recreated by the monitor along with all persistent processes hosted in that node.

To reduce the fault zone impact, this change removes the soft node down/up functionality so that the DTM process is recreated without killing all other processes in the node. The rule where the persistent DTM process cannot be restarted within the configured retries in the specified time window will cause a node down will still be enforced.