add shutdown script

common/docscoapi.js

-"use strict";
+"use strict";
 
 (function(window, undefined) {
   'use strict';
@@ -1276,7 +1276,7 @@
         }
       }
       t._state = ConnectionState.Reconnect;
-      var bIsDisconnectAtAll = t.attemptCount >= t.maxAttemptCount;
+      var bIsDisconnectAtAll = (4001 === evt.code || t.attemptCount >= t.maxAttemptCount);
       if (bIsDisconnectAtAll) {
         t._state = ConnectionState.ClosedAll;
       }
@@ -1284,7 +1284,7 @@
         t.onDisconnect(evt.reason, bIsDisconnectAtAll, t.isCloseCoAuthoring);
       }
       //Try reconect
-      if (t.attemptCount < t.maxAttemptCount) {
+      if (!bIsDisconnectAtAll) {
         t._tryReconnect();
       }
     };