patch 7.4.2117
Problem:    Deleting an augroup that still has autocmds does not give a
            warning.  The next defined augroup takes its place.
Solution:   Give a warning and prevent the index being used for another group
            name.
diff --git a/src/version.c b/src/version.c
index f797f41..962bae7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -759,6 +759,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2117,
+/**/
     2116,
 /**/
     2115,