Update runtime files.
diff --git a/runtime/doc/vi_diff.txt b/runtime/doc/vi_diff.txt
index cb3b241..8872103 100644
--- a/runtime/doc/vi_diff.txt
+++ b/runtime/doc/vi_diff.txt
@@ -1,4 +1,4 @@
-*vi_diff.txt* For Vim version 8.1. Last change: 2019 May 13
+*vi_diff.txt* For Vim version 8.1. Last change: 2019 Sep 27
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -703,7 +703,7 @@
CTRL-A works like CTRL-@ but does not leave insert mode.
-CTRL-R {0-9a-z..} can be used to insert the contents of a register.
+CTRL-R {register} can be used to insert the contents of a register.
When the 'smartindent' option is set, C programs will be better auto-indented.
With 'cindent' even more.