Creating clients duplicates url namespace

[lindyhopchris]

It seems strange to do the following:

$g = new GuzzleHttp\Client(['base_uri' => 'http://localhost/data/resources/']);
$client = json_api('default')->client($g);

when the config for the default API has the namespace as /data/resources. This would be better:

// $options is other guzzle options (optional)
$client = json_api('default')->client('http://localhost', $options);