Disable automatic building of iOS tests

Merge pull request ReactiveCocoa#36 from ReactiveCocoa/pacify-xcode

Pacify Xcode

Merge pull request ReactiveCocoa#35 from ReactiveCocoa/carthage-0.5

Migrate to Carthage 0.5

Merge pull request ReactiveCocoa#33 from ReactiveCocoa/cartfile

Use Carthage to manage submodules

Remove RVMViewModel.model property

++RAC v2.1.4

Initial release, tagged to RAC 2.0