patch 9.0.0006: not all Visual Basic files are recognized

Problem:    Not all Visual Basic files are recognized.
Solution:   Change detection of *.cls files. (Doug Kearns)
diff --git a/src/version.c b/src/version.c
index 0e6758f..98227fa 100644
--- a/src/version.c
+++ b/src/version.c
@@ -736,6 +736,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    6,
+/**/
     5,
 /**/
     4,