Vim 8.1 release

Update version number and information.  Fix a couple of tests.
diff --git a/runtime/doc/repeat.txt b/runtime/doc/repeat.txt
index 6281040..6246478 100644
--- a/runtime/doc/repeat.txt
+++ b/runtime/doc/repeat.txt
@@ -1,4 +1,4 @@
-*repeat.txt*    For Vim version 8.0.  Last change: 2018 Mar 04
+*repeat.txt*    For Vim version 8.1.  Last change: 2018 Mar 04
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar