updated for version 7.4.503
Problem:    Cannot append a list of lines to a file.
Solution:   Add the append option to writefile(). (Yasuhiro Matsumoto)
diff --git a/src/testdir/test_writefile.ok b/src/testdir/test_writefile.ok
new file mode 100644
index 0000000..dfb6a2b
--- /dev/null
+++ b/src/testdir/test_writefile.ok
@@ -0,0 +1,5 @@
+hello
+world!
+good
+morning
+vimmers