[test]fix test case file dialog
[test] fix manual test case
update README.md
[win] fix that setAlwaysOnTop doesn't work when application isn't focused

  fix #655
[test] test case for #655
Merge pull request #657 from owenc4a4/i655

[win] fix that setAlwaysOnTop doesn't work when application isn't focuse...
Merge pull request #658 from owenc4a4/test

[Test] fix bug of some test, add test case for #655