patch 7.4.741

Problem:    When using += with ":set" a trailing comma is not recognized.
            (Issue 365)
Solution:   Don't add a second comma. Add a test. (partly by Christian
            Brabandt)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    741,
 /**/
     740,
 /**/