#335 handle stream/resource in upload/download

[quazardous]

Using downloadStream() with a file is like

$charset = null;
$docToDownload->downloadStream($fh = \GuzzleHttp\Psr7\Utils::tryFopen($filename, 'w'), $charset);

[jlevers]

@quazardous are you still interested in getting this over the line? just checking because i'm going to finish it if not :)

[quazardous]

I've been busy, but it's in a corner of my mind 😋

[quazardous]

@jlevers I've pushed the changes requested (I hope)