Add RACCommand support to UIAlertView
Improve docs for UIAlertView.rac_command.
Clean up UIAlertView+RACCommandSupport.

Also adds a warning if the delegate is non-nil when hijacking.
Document that UIAlertView.rac_command overrides the delegate
Unset alert view delegate when unsetting command.
Improve docs for UIAlertView+RACCommandSupport.
Unset the associated object when unsetting the delegate
Added change dictionary to -rac_addObserver:forKeyPath:willChangeBlock:didChangeBlock: blocks.
Merge branch 'racobserve' into racobserve-change-dictionary

Conflicts:
	ReactiveCocoaFramework/ReactiveCocoa/NSObject+RACKVOWrapper.m
	ReactiveCocoaFramework/ReactiveCocoa/NSObject+RACPropertySubscribing.m
Added -rac_changesForKeyPath:observer: and deprecated rac_signalWithChangesFor:keyPath:options:observer:.
Changed the new RACKVOWrapper method to take only one block and accept arbitrary KVO options.
Deprecate -rac_addObserver:forKeyPath:options:block:.
Merge branch '2.0-development' into racobserve-change-dictionary
Merge branch '2.0-development' into racobserve-change-dictionary
Fix the test for intermediate path components.
Fix the disposable not being removed when disposed.
Merge branch '2.0-development' into racobserve-change-dictionary

Conflicts:
	ReactiveCocoaFramework/ReactiveCocoa/NSObject+RACKVOWrapper.m
	ReactiveCocoaFramework/ReactiveCocoaTests/RACKVOWrapperSpec.m
Renamed RAC specific KVO change dictionary keys.
Clarified docs.
Always include RAC specific KVO change dictionary values.