Better cabcar support

[notsoimmersiverailroader]

Describe the suggestion
A type of car that can access the locomotive's controls without actually being a locomotive so that villagers treat it like a regular passenger car Applications of the suggestion
Improves immersion, gives pack creators additional options when designing subway or push-pull trains, saves on fuel and steel for survival players,

[km00700]

This is a thing for the test build already