patch 9.0.1647: insufficient testing for syntax plugins

Problem:    Insufficient testing for syntax plugins.
Solution:   Add shell file examples. (Charles Campbell)  Create a messages
            file for easier debugging and reporting the test results.
diff --git a/src/version.c b/src/version.c
index 24ce994..b027efd 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1647,
+/**/
     1646,
 /**/
     1645,