CURLResponse is private
Remove old header-parsing APIs
Shift off HTTP parsing routines to a more appropriately named file
Delete old resumable uploader
Place our NSURLRequest extensions in CURLRequest file
Remove unecessary setting of .shouldUseCurlHandle property
Shift NSURLRequest.shouldUseCurlHandle back over to CURLProtocol
Flesh out CURLProtocol docs a bit
Make registration of CURLProtocol the client's problem to deal with

This may seem annoying now, but Apple could change things in the future
to make this change worthwhile!