patch 7.4.964

Problem:    Test 87 doesn't work in a shadow directory.
Solution:   Handle the extra subdirectory. (James McCoy, closes #515)

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    964,
 /**/
     963,
 /**/