updated for version 7.4b.015

Problem:    Can't compile without the 'acd' feature.
Solution:   Add #ifdefs. (Kazunobu Kuriyama)

src/version.c

@@ -727,6 +727,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    15,
 /**/
     14,
 /**/