Prebuilt Frameworks & Tagged Releases

[msanders]

This would speed up building via Carthage by quite a bit, since it automatically downloads those if they exist instead of building from scratch each time. Shouldn't be too hard to do manually, but can also be done automatically via Travis's tagged releases. Examples include: Quick, Nimble, and Carthage itself. Thanks for the great library!

[Vinzius]

:+1: for tags like "3.2" instead of "Version_3.2", thanks :)