Revert "Merge branch '781-mime-stream-pair' of git://github.com/plausiblelabs/AFNetworking"

This reverts commit f7d98aac9cd615eab4d70d6826f4ce907514dcf6, reversing
changes made to 9b2a20c0a130104b2e792ab62b6c8cc8238323f1.

Conflicts:

	AFNetworking/AFHTTPClient.m
Merge pull request #1044 from AFNetworking/experimental-revert-multipart-stream-provider

Revert Multipart Form Stream Provider