Add RestUpload::waiting() to set connect and read timeouts

[thekid]

Complements RestRequest::waiting() - see #24

use io\File;
use webservices\rest\Endpoint;

$file= new File($reference);

$endpoint= new Endpoint('https://api.example.com/v1');
$response= $endpoint->resource('images/edits')
  ->upload(method: 'POST')
  ->waiting(read: 600)
  ->transfer('images[]', $file->in(), $file->filename)
  ->pass('prompt', 'This image but all people are Simpsons characters')
  ->finish()
;