patch 7.4.1811

Problem:    Netbeans channel gets garbage collected.
Solution:   Set reference in nb_channel.

src/version.c

@@ -753,6 +753,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1811,
 /**/
     1810,
 /**/