Don't Penalize U-Turns at Turning Circles

Would it be hard to let valhalla use turning circles (`highway=turning_circle`), if they can help saving time?

Here is an example: I'm starting at the marker with the red arrow, facing in the direction of the red arrow. Since it is a dead-end, valhalla will guide until the end of the road, turn around and then drive to my destination, which is the upper marker. For routing on a device this will be confusing, since we are ignoring the turning circle, which probably is better suited to do the turn.
Here is the request body of my example:
```
"locations": [
{"lon": 7.00794, "lat": 51.66954, "preferred_side" : "same"},
{"lon": 7.00805, "lat": 51.66998}

],
"costing": "auto"
```