patch 7.4.1360

Problem:    Can't remove a callback with ch_setoptions().
Solution:   When passing zero or an empty string remove the callback.

src/version.c

@@ -747,6 +747,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1360,
 /**/
     1359,
 /**/