updated for version 7.3.509
Problem:    ":vimgrep" fails when 'autochdir' is set.
Solution:   A more generic solution for changing directory. (Ben Fritz)
diff --git a/src/version.c b/src/version.c
index 7e77f9a..4c90c99 100644
--- a/src/version.c
+++ b/src/version.c
@@ -715,6 +715,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    509,
+/**/
     508,
 /**/
     507,