Created the Geocoding tutorial in Swift

I'm going to change this to use the initializer syntax -
`var tiledLayer = AGSTiledMapServiceLayer(URL: url)`

Per Apple's doc, the obj-c factory methods can be used as swift initializers. 
>For consistency and simplicity, Objective-C factory methods get mapped as convenience initializers in Swift. This mapping allows them to be used with the same concise, clear syntax as initializers. 
https://developer.apple.com/library/prerelease/mac/documentation/Swift/Conceptual/BuildingCocoaApps/InteractingWithObjective-CAPIs.html