Setup console.log() for TVJS apps

Example.swift

func appController(appController: TVApplicationController, evaluateAppJavaScriptInContext jsContext: JSContext) {
    jsContext.evaluateScript("var console = {log: function() { var message = ''; for(var i = 0; i < arguments.length; i++) { message += arguments[i] + ' ' }; console.print(message) } };")
    let logFunction: @convention(block) (NSString!) -> Void = { (message:NSString!) in
        print("JS: \(message)")
    }
    jsContext.objectForKeyedSubscript("console").setObject(unsafeBitCast(logFunction, AnyObject.self), forKeyedSubscript:"print")
}