PHP errors are now handled as exception

We set an error handler to turn any unsuppressed PHP error
into an exception, including notices, warning, strict, etc.

Background

We want to catch and log file_get_contents issues, like this one from /pads:
failed to open stream: HTTP request failed! HTTP/1.1 502 Bad Gateway

How to use it

This allows constructions like:

try {
    // Code
} catch (ErrorException $ex) {
    // Handles exception
}