Add test framework

[daniel-samson]

Can we add phpunit or codeception?

[daniel-samson]

maybe travis ci integration?

[michaelfranzl]

It would be the right thing to do. This would involve setting up two webservers (one for no.php and one for proxied content), then testing each use case via HTTP(s) via the no.php server. Unfortunately, I won't be able to to this any time soon. Contributions are welcome.