patch 9.0.1402: crash when using null_class

Problem:    Crash when using null_class.
Solution:   Give an error when trying to use a null class.
diff --git a/src/version.c b/src/version.c
index 0265c47..2dca10d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1402,
+/**/
     1401,
 /**/
     1400,