open the in-memory output stream immediately when scheduling it on the run loop
- if never opened (as was the case if no response was received) apparently calling close will not implicitly remove the stream from the runloop (apple docs are misleading?)
Petty DRY refactoring of basic request methods.
Merge pull request #2257 from larsacus/master

Petty DRY extraction of basic session data task creation in request methods
Further refactoring AFHTTPSessionManager
[Issue #2229] Handling request serialization errors in refactored AFHTTPSessionManager
Merge pull request #2178 from jtomson/fix_outputstream_leak

Fix AFConnectionOperation outputStream leak if no response is received
[Issue #2187][Issue #2245][Issue #2255] Adding image cache and response serializer properties to UIButton category, as well as cancelling image request operations correctly on a per-state basis

Changing signature of success blocks in UIButton category to be consistent with those of UIImageView category
Merge branch 'master' of github.com:AFNetworking/AFNetworking
[Issue #2240] Replacing MAX_ALLOWED macro with MIN_REQUIRED
Whitespace
Update CHANGES
Bumping version to 2.4.0
Explicitly casting UIControlState to NSUInteger in format argument