Support for multipart/form-data requests

[akashivskyy]

ResponseDetective should support multipart/form-data requests, deserializing each data segment as if they were at the root level.

The output of body section should provide information on all segments:

Segment 0
 ├─ Headers
 │ Content-Type: image/png
 │ Content-Disposition: form-data; name="foo"; filename="image.png"
 ├─ Body
 │ 10px × 10px image

Segment 1
 ├─ Headers
 │ Content-Disposition: form-data; name="bar"
 ├─ Body
 │ baz

Segment 2
 ├─ Headers
 │ Content-Type: application/octet-stream
 │ Content-Disposition: form-data; name="qux"
 ├─ Body
 │ <none>