The response a RouteService.Solve opertaion will return when it fails.
 /// <summary>Creates a new instance.</summary>
 /// <param name="errorResponse">The REST response.</param>
 public SolveException(SolveErrorResponse errorResponse)
     : base(errorResponse.error.message)
 {
 }
 /// <summary>Creates a new instance.</summary>
 /// <param name="errorResponse">The REST response.</param>
 public SolveException(SolveErrorResponse errorResponse) : base(errorResponse.error.message)
 {
 }