Add __toString behaviour for the URL object

Signed-off-by: Stéphane HULARD <s.hulard@chstudio.fr>
Update toString behaviour with the __toString one

Signed-off-by: Stéphane HULARD <s.hulard@chstudio.fr>
Add tests on all kind of requests

Signed-off-by: Stéphane HULARD <s.hulard@chstudio.fr>