Add a "unrestricted" category to logistics zone

The logistics zone in game now (0.7.9) is kinda akward to use.
Usually by adding logistics zone, you want to restrict car's moving range, but don't want some critical lifelines on wheels to be cut instantly.
(e.g. potatos from mutiple farms to food market, delivered dierctly by truck)
Now with logistics zone seperating them apart, ANY material flow requires 4 additional storage unit (2 on each side) and a dedicated export route.
that means tons of space usage and building cost, making logistics zone a tough choice to transition to.
So i suggest adding a default "Unrestricted" category to logistics zones. Vehicles assigned to it can access the whole map at a lower priority.
They act as if there isn't any logistics zone at all, and can carry on the previous long-range delivery jobs.
While other vehicles in a proper zone can handle short tasks effectively.
This will add a gradient for players to intoduce logistics zones into their gameplay.