Add-on vehicle behaving weird

[R4ven47]

After requesting a model and using setElementModel
on every client, player reports issue of seeing vehicle doors constantly moving.
Other issues include: 'Network Trouble' when player tries to get inside vehicle

To reproduce

1. Download the reproduction resource
2. Create a vehicle server-side and enter it
3. Use '/request' command
4. See bug
   Reproduction resource:
   model_requesting.zip

Expected behaviour
Normal vehicle doors movement in all clients with the ability of players getting into the vehicle.

- server/client version: 1.5.8

[Allerek]

'Add-on' vehicles are not ready, they are still being in a recode process, we shouldnt care about current system much, as its being reworked.
#1936
#1924