updated for version 7.4.508

Problem:    When generating ja.sjis.po the header is not correctly adjusted.
Solution:   Check for the right header string. (Ken Takata)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    508,
 /**/
     507,
 /**/