Change vehicle behavior in the route rail

[elliottwilliams]

• Vehicles should move along the rail to a point in-between two stations when a vehicle has departed a station and is not yet arriving at its next station.
  • Write a function to determine if a vehicle is considered "arriving".
• Stack multiple vehicle dots on top of each other if they occupy the same "space" on the rail. It should be visually clear that multiple vehicles are in the same area.
• Selecting a vehicle dot (or stack) should open a popover containing the vehicle names, with a "more info" button. Selecting this button should embed the vehicle view(s) from Rewrite Vehicle view to be inline #7 into the route table, and the rail should expand, with each vehicle dot being positioned in the upper-right corner of its view.