Add proper file upload support to Turbo by supporting multipart/form-data.  Correctly parse form-data boundaries and decode name value data into the arguments table as tables withe the data in [1] and form-data field values in the hash.  Handle unescaping content-type javascript and json values and decode content-transfer-type base64; binary content-transfer-type is also supported.  The base64 encoding rather than binary may be more compatibile with some browsers that for example don't support XHR2, where the form-data has to be manually encoded in the XMLHttpRequest using javascript.