Tutorial - enhancements for languages and URL hash

[rmglennon]

Some feedback from @burritojustice for the tutorial (source file: https://github.com/valhalla/valhalla-docs/blob/master/add-routing-to-a-map.md)

1. Show how to switch languages. Code from tutorial is something like this:

    L.Routing.control({
      waypoints: [
        L.latLng(41.8758,-87.6189),
        L.latLng(33.8128,-117.9259)
      ],
      lineOptions: {
        styles: [ {color: "white",opacity: 0.8, weight: 12},
                {color: "#2676C6", opacity: 1, weight: 6}
      ]},
      router: L.Routing.mapzen("your-api-key", {costing:"auto"}),
      formatter: new L.Routing.mapzenFormatter(),
      summaryTemplate:'<div class="start">{name}</div><div class="info {costing}">{distance}, {time}</div>',
      routeWhileDragging: false
    }).addTo(map);

2. Add ability to use a URL hash to re-create the route. Mapzen.js has this capability. I think the hash will be easier to get after lrm-mapzen is integrated into mapzen.js.