Add a function to AsyncQueue to tell if we are connected

asyncqueue.c

@@ -1238,3 +1238,14 @@ void *AsyncUnitGetQueueContext(pAsyncUnit unit)
   assert(unit->queue);
   return unit->queue->context;
 }
+
+
+int AsyncUnitIsQueueConnected(pAsyncUnit unit)
+{
+  assert(unit);
+  assert(unit->queue);
+  if (unit && unit->queue)
+    if (unit->queue->state == eAsyncConnected)
+      return 1;
+  return 0;
+}