startNavigation
abstract fun startNavigation(origin: Coordinate? = null, destination: Coordinate, travelMode: TravelMode = TravelMode.Walk(), options: NavigationOptions = NavigationOptions(), searchRules: ItinerarySearchRules = ItinerarySearchRules(), timeout: Long = 30): Single<Navigation>
abstract fun startNavigation(itinerary: Itinerary, options: NavigationOptions = NavigationOptions(), searchRules: ItinerarySearchRules = ItinerarySearchRules()): Single<Navigation>