Implemented assigning and using private AVs
With this commit, ownership of pravs (private AVs) is assigned to agents and pravs can be choosen during mode choice and routed on the network and simulated in Qsim.
Currently pravs have the same attributes as cars.
But still to do are: Flow Efficiency Calculator for pravs Utility parameters for pravs that are different from cars
And then for the 2030 Scenario: creating networks with permissions for different pravs based on link and prav type