Included patch for persistent undo.  Lots of changes and added test.
diff --git a/src/testdir/Makefile b/src/testdir/Makefile
index 6a8e85f..53e0854 100644
--- a/src/testdir/Makefile
+++ b/src/testdir/Makefile
@@ -69,7 +69,7 @@
 		  fi \
 		else echo $* NO OUTPUT >>test.log; \
 		fi"
-	#-rm -rf X* test.ok viminfo
+	-rm -rf X* test.ok viminfo
 
 test49.out: test49.vim