updated for version 7.3.684
Problem:    "make test" does not delete lua.vim.
Solution:   Add lua.vim to the clean target. (Simon Ruderich)
diff --git a/src/testdir/Make_dos.mak b/src/testdir/Make_dos.mak
index 487ecd8..b52f249 100644
--- a/src/testdir/Make_dos.mak
+++ b/src/testdir/Make_dos.mak
@@ -62,6 +62,7 @@
 	-if exist tiny.vim del tiny.vim
 	-if exist mbyte.vim del mbyte.vim
 	-if exist mzscheme.vim del mzscheme.vim
+	-if exist lua.vim del lua.vim
 	-del X*
 	-if exist viminfo del viminfo