Fix request stream exhaustion error by copying the original NSInputStream
[Issue #715] Fixing warnings generated by earlier versions of Xcode (/cc Ignacio Rodrigo)

Minor reformatting
Merge branch 'stream_exhausted_fix' of https://github.com/aburgel/AFNetworking into aburgel-stream_exhausted_fix
Minor reformatting
Re-ordering NSURLConnectionDelegate method implementations
Marking connection parameter in connection:needNewBodyStream: as __unused
[Issue #719] Adding shouldUseCredentialStorage property to AFURLConnectionOperation /thanks Xihe Yu
Updating list of implemented NSURLConnectionDelegate method