Documentation on ManeuverType is outdated

[erikvullings]

While using Jelmer's Rust-based client to query Valhalla's routing interface, I received many JSON serialization errors due to the fact that not all ManeuverType options were implemented. As it turned out, however, even the Valhalla API documentation does not mention them all. The actual list of values, as implemented in the code, can be found here. Therefore, please add the missing enum values to your documentation, specifically:

• kElevatorEnter (value 39)
• kStepsEnter
• kEscalatorEnter
• kBuildingEnter
• kBuildingExit