Adding comma (,) as a percent escaped character since it's in the reserved words per the RFC
Fixes -[AFURLConnectionOperation totalBytesRead] threading issue.
Adding missing #pragma clang diagnostic pop (/thanks @tewha)
[Issue #817] Removing unused totalContentLength and offsetContentLength properties, and implementation of -connection:didReceiveResponse:
[Issue #803] Only set image in UIImageView category if non-nil

Signed-off-by: Mattt Thompson <m@mattt.me>