Use networkMode in vehicle Definitions

[paulheinr]

For now, the router uses the id of a vehicle type, but networkMode should be used.

[Janekdererste]

As we have removed the router for now, this is no longer part of MVP Qsim. I am closing this issue, because the vehicle implementation has changed in #99 .

In case we implement another router, we can use the vehicle definition which is there directly, or improve on it