* Update docs/request.md
* Bring some sanity to request parsing and error handling
- The browser can do JSON parsing itself. Let's defer to that where
possible. (A few IE hacks are required here, though.)
- Don't propagate any error that occurs before `deserialize`/`extract`.
- Allow sending raw array buffers/blobs/etc. to `deserialize`.
- Align behavior more closely with the XHR spec.
- Send the more useful parsed response to `deserialize`, not the less
useful string response.
I basically recast it to remove 99% of the duplication. They're
basically the same function mod how they fire their requests and append
query parameters.
