Use -rac_description to prevent unwieldly backtraces
Merge pull request #683 from ReactiveCocoa/sprinkle-rac_description-master

Use -rac_description on master
Merge branch 'master' into sprinkle-rac_description

Conflicts:
	ReactiveCocoaFramework/ReactiveCocoa/UIControl+RACSignalSupport.m
	ReactiveCocoaFramework/ReactiveCocoa/UIGestureRecognizer+RACSignalSupport.m
	ReactiveCocoaFramework/ReactiveCocoa/UITextField+RACSignalSupport.m
	ReactiveCocoaFramework/ReactiveCocoa/UITextView+RACSignalSupport.m