Removed unnecessary willChangeValueForKey and didChangeValueForKey method calls.
Fix a bug where [AFURLConnectionOperation pause] did not correctly reset
the state of AFURLConnectionOperation, causing the Network Thread to
enter an infinite loop.

The logic for 'pause' was calling [self.connection performSelector:...].
If 'pause' is executed immediately after 'start', and 'start' did not
have a chance to create self.connection on the Network Thread, then the
logic in 'pause' would effectively be a no-op. When 'resume' gets
called, the previous connection was not actually cancelled, so there are
2 connections both of which have a reference to the same NSOutputStream.
The first connection to finish/error would close the NSOutputStream, and
the second connection would spin forever in the delegate callback
connection:didReceiveData: since [self.outputStream hasSpaceAvailable]
always returns NO.

The test case I added reproduces the failure, but is flaky because it
relies on a race condition between the main thread and the Network
Thread.
Fix a bug where [AFURLConnectionOperation cancel] does not set the
appropriate error on the NSOperation.

There is a race condition where 'cancel' is called immediately after
'start'. When operationDidStart is then called on the Network Thread,
self.connection is not instantiated, because the NSOperation is
cancelled, and 'finish' is called, but without the error set.  When
cancelConnection is then called on the Network Thread, the error is not
set, because the operation is already finished.

In the new code, cancelConnection is always responsible for setting the error,
and then calling 'finish'. operationDidStart never attempts to call
'finish'.

This bug was one of the sources of non-deterministic failures in
testThatCancellationOfRequestOperationInvokesFailureCompletionBlock.
Fixed refs to AFJSONSerializer -> AFJSONResponseSerializer
Removing .swp files from example
posting AFNetworkingTaskDidFinishNotification on main thread is now guaranteed and no longer breaks AFNetworkActivityIndicatorManager
Adding initializers that allow a user to create a AFURLSessionManager that will suspend its delegate queue upon being decoded.
Refactoring code into its own method to allow a user to associate a progress object and a completion handler with a specified upload task.
Adding an initializer to AFHTTPSessionManger control if it should start the delegate operation queue in a paused state after being decoded.
Calling the wrong initializer.
[Issue #1562] Setting default security policy on AFURLSessionManager, rather than AFHTTPSessionManager
Merge branch 'master' of github.com:AFNetworking/AFNetworking
Merge pull request #1560 from kubbing/master

posting AFNetworkingTaskDidFinishNotification on main thread
Remove deletion of all task delegates in URLSessionDidFinishEventsForBackgroundURLSession:

This should not happen because sometimes this method is called after waking the app up to
respond to authentication challenges and no tasks have completed yet.  It is not safe to
assume that all tasks are complete and the delegates should be removed.  Doing some
results in orphaned tasks with AF delegates to handle them.

Task delegates already get deleted after the URLSession:task:didCompleteWithError: call
which will be made for each task.

Issue: 1579
[Issue #1585] Documenting default Accept header field value for setImageWithURL:, et al.
Fixed issue where the query string serialization block was not used
Merge pull request #1548 from maxgoedjen/master

Fixed refs to AFJSONSerializer -> AFJSONResponseSerializer
Merge pull request #1552 from troupe/master

Removing .swp files from example
[Issue #1552] Removing remaining references to .swp files in project
Adding spaces to image/* to avoid warning about /* inside comment block