Port code depending on RACAble to use RACObserve instead.
Change NSObjectRACPropertySubscribingExamples to account for initial value being sent on subscription.
Merge branch 'racobserve' into racobserve-change-dictionary

Conflicts:
	ReactiveCocoaFramework/ReactiveCocoa/NSObject+RACKVOWrapper.m
	ReactiveCocoaFramework/ReactiveCocoa/NSObject+RACPropertySubscribing.m
Added an iOS App target and a test target for UIKit testing.
UITextViewRACSupportSpec fails?
Fixed broken tests, thanks @kastiglione.
Added -rac_changesForKeyPath:observer: and deprecated rac_signalWithChangesFor:keyPath:options:observer:.
Rename `-ignoreElements` to `-ignoreValues`
Deprecate -ignoreElements
Changed the new RACKVOWrapper method to take only one block and accept arbitrary KVO options.
Deprecate -rac_addObserver:forKeyPath:options:block:.
Replace some left over uses of RACAble.
Merge pull request #601 from ReactiveCocoa/racobserve

Add RACObserve as default KVO observation method.
Publicize UIActionSheet+RACSignalSupport.h
Remove managing delegate assignment from RACDelegateProxy
Merge pull request #629 from ReactiveCocoa/rename-ignoreElements

Rename -ignoreElements to -ignoreValues
Merge pull request #611 from ReactiveCocoa/uiactionsheet-signal-support

Add -[UIActionSheet rac_buttonClickedSignal]
Merge remote-tracking branch 'origin/2.0-development' into pr/626

Conflicts:
	ReactiveCocoaFramework/ReactiveCocoa.xcodeproj/project.pbxproj
Expose scheme for new test host target
Merge branch '2.0-development' into racobserve-change-dictionary