allow declaring traci permission changes as transient

[namdre]

so that they can be ignored, in the same way as rerouter-based permission changes.
To be used with #13494

[namdre]

Either: by adding an optional flag to all of the allow/disallow methods
(4 lane methods and 4 edge methods due to supporting allow/disallow with a string and a stringList)

Or: by setting something like a permission mode that influences subsequent calls to setAllowed and setDisallowed

@behrisch which would would you prefer?

[behrisch]

I would prefer the flag. Changing the function signature is not the worst thing here but we need to change the protocol. Nevertheless I think it is preferable to have it as stateless as possible.