Catch Throwable instead of Exception (for PHP7)

With PHP7 it is now possible to catch all types of errors by catching Throwable. This middleware should be changed accordingly.

Has this become a configuration option yet?

I'm not really maintaining this package anymore as stackphp has been superseded by PSR-15.
But if you need it, you can open a PR and I'll hapilly accept it.
Just make sur to catch both \Exception and \Throwable so that it works in both PHP 5 and PHP 7.