Consider using Scrutinizer and displaying corresponding badges

[localheinz]

I think @Ocramius and I agree that is a good idea to use Scrutinizer (or a similar tool) for performing code quality / coverage checks in addition to what we already have, and then also display the corresponding badges in README.md.

However, setting this up requires ADMIN privileges, so if anyone with those would be willing to set it up, that would be awesome!

See #453 (comment).

/cc @EvanDotPro @ezimuel @weierophinney

Scrutinizer

[localheinz]

@GeeH

I also wouldn't mind using Code Climate instead!