Support http proxy

[nighon]

Just added feature supporting http proxy

add HTTP_PROXY inside .env

HTTP_PROXY=http://proxyhost:port

add config file goutte.php

<?php

return [
    'http_proxy' => env('HTTP_PROXY'),
];

[dweidner]

I would like to allow users to customize all available options of the Goutte client (see #18). Would it be possible, to simply call config('goutte') to retrieve the entire array defined in the config file?

[dweidner]

I have provided a new feature branch (feautre/config). Would be great if you could check that out and provide some feedback.

[nighon]

Yes, I have checked the code of branch feature/config. Everything is ok after I moved the directory config inside src.

Your solution is better than mine!

[dweidner]

Thank you for the hint, I fixed the path of the package configuration file

[dweidner]

Merged the latest feature branch