Form Data Upload Support

[blakerobertson]

Currently, everything sent in the body of the PUT request is piped over to the GET side, but it would be helpful, for uploading from a webapp, if we could send files as form-data.

For example, a PUT request body like this:

------WebKitFormBoundarynZ754E75uK8wQZf9
Content-Disposition: form-data; name="file"; filename="testfile.psv"
Content-Type: application/octet-stream

1|2|3|4|5|data

------WebKitFormBoundarynZ754E75uK8wQZf9--

would result in the following coming out on the GET side:

1|2|3|4|5|data