patch 7.4.1299

Problem:    When the server sends a message with ID zero the channel handler
            is not invoked. (Christian J.  Robinson)
Solution:   Recognize zero value for the request ID.  Add a test for invoking
            the channel handler.

src/version.c

@@ -747,6 +747,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1299,
 /**/
     1298,
 /**/