updated for version 7.4.503

Problem:    Cannot append a list of lines to a file.
Solution:   Add the append option to writefile(). (Yasuhiro Matsumoto)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    503,
 /**/
     502,
 /**/