2.0.0-beta.1

This is the first beta pre-release version of Alamofire-SwiftyJSON 2.0.0.

Compatible with Swift 3.0.2, SwiftyJSON 3.0+ and Alamofire 4.0+.

Much special thanks @jregnauld, @rokgregoric and @wongzigii for their works. 🎉🎉