iOS Sandbox

- Codable Playground: Test mapping with new Swift4 Codable interface and URLSession
- Bezier Path Playground: Test arcs, lines and masks with UIBezierPath and CAShapeLayer
- CGRect Playground: Test CGRect functionality and CATransform and CGAffineTransform
- Sandbox/GithubSearch: Sample Github repo search master-detail view with Alamofire, Coredata and Codable
- DynamicDispatch Playground: Test dynamic dispatch, associatedtype and generics
- GCD Playground: Test serial, concurrent queues and .barrier flag