Make it possible to search rides through text input

[rolfhermancoen]

Idea I've seen this concept used in the new Scenery view, where it is possible to filter/find something through the use of a text input. This could maybe also be useful for the RideVehicleEditor, especially when there are quite some rides in the park.

The scenery window also has a "Clear" button, which could also provide some usefulness.

Additional context