DDLProc/DMLProc must return a meaningful error if a local/remote workernode/controllernode was restarted

DMLProc, DDLProc don’t reestablish connections to WriteEngines if they fail so they won’t survie WriteEngine restart. DMLProc/DDLProc must survive this outage with failing their current operations before they reestablish their connections. The user must be notified about the operations failure.

Update: Make sure columnstore services survive restarts of other services as well, including controllernode, workernode, primproc, and exemgr restarts.