Remove try/catch
Revert "Remove try/catch"

This reverts commit c239e15ce51cd725e6645f519f0c759debc7b9fc.
Merge branch 'master' of git://github.com/AFNetworking/AFNetworking
Don't update NSProgress for data tasks

1. Progress is never returned by data task methods, only download methods. Those methods update the progress elsewhere so removing this shouldn't affect them.
2. The totalUnitCount is never being set during data tasks, so even if it was being returned, the NSProgress always reports a fractionCompleted of 0 right now.
3. There is a crash that occurs here rarely. My best guess is that the delegate is still being sent messages as it's being released.
Merge branch 'master' of github.com:PadraigK/AFNetworking into PadraigK-master
[Issue #1675] Adding attemptsToRecreateUploadTasksForBackgroundSessions property
Merge branch 'master' of git://github.com/AFNetworking/AFNetworking
UIKit requires that the completionHandler for application:handleEventsForBackgroundURLSession:completionHandler be called on the main thread.

http://developer.apple.com/library/etc/redirect/xcode/ios/889e4b/documentation/Foundation/Reference/NSURLSessionDelegate_protocol/Reference/Reference.html
Adding tests for URLSession manager upload/download task progress
check self.uploadProgress inside of dispatch_async

Check self.uploadPorgess is nil or not inside dispatch_async block.
If self.uploadProgress is checked outside of dispatch_async block,
thread can not guaranteed self.uploadPorgress is not nil.

Signed-off-by: Kyungkoo Kang <kyungkoo.kang@yahoo.com>
Making URLSession task progresses comply with NSProgress composition
Add an explanation of Reachability.
Remove empty line noise.
Update CONTRIBUTING.md
Extension for WebFrame loadRequest
UIImageView allows weaker serializer subclasses

Weakened serializer from subclasses of AFImageResponseSerializer to any
class conforming to AFURLResponseSerialization protocol.
This allows compound serialiers to be set for handling different image
types, like gifs and normal images.
Prevents NSNotification from firing twice, when the reachability status changes.
Merge pull request #2113 from SSA111/master

Prevents NSNotification from firing twice, when the reachability status ...
Adding explicit @synthesize for streamStatus & streamError properties

Signed-off-by: Mattt Thompson <m@mattt.me>
Merge branch 'master' of github.com:AFNetworking/AFNetworking