patch 9.0.1229: Cap'n Proto files are not recognized

Problem:    Cap'n Proto files are not recognized.
Solution:   Add a pattern and the "capnp" filetype. (Amaan Qureshi,
            closes #11862)
diff --git a/src/version.c b/src/version.c
index 361567b..80d8444 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1229,
+/**/
     1228,
 /**/
     1227,