[2.0.23] Smart belt will place additional underground entrance at start point

[CoUsT]

Hard to explain so please watch attached 5 seconds video.

Basically if you move belt over obstacle then underground belt at 90 angle then another obstacle then it will spawn 2 underground belts next to each other instead of a single one.

[Loewchen]

What is needed is a non-belt obstacle with a one tile gap into a belt running orthogonal. The additional entrance will be placed at the starting point of the drag.