Formal implementation of dynamic congestion pricing: demo should be updated too

[toruseo]

Currently, congestion pricing is partially implemented through Link.route_choice_penalty. However, API is not fully implemented and the toll is static. Formal implementation of dynamic congestion pricing is planned.

DTA solvers should support this feature as well.

[toruseo]

Implemented.

The advanced demo and DTA demo should be updated accordingly, but this is a future task

[EwoutH]

Quite cool, awesome to see UXsim keep being developed!