Add speed limit attribute

[ampersand38]

When merged this pull request will:

• Add slider attribute to control vehicle speed limit
• Useful for matching vehicle speed to infantry, paradrop, heli search, etc
• https://www.youtube.com/watch?v=8V0OTt6pVrE
• Close Limit vehicle speed module #605

I messed up #648 and a new pr seemed like the easiest way to fix it.
Attribute toggle settings split to #716

[rautamiekka]

I wonder if spawn would speed things along ?

^ Granted, my laptop doesn't run both the game and the Server instance simultaneously especially fast, and on it I noticed that forEach+spawn takes a noticeable time to get things done compared to call, like CBA_fnc_setLoadout can take something like 400-600ms (looks like it) to get the squad equipped (which also happens in a random order) instead of next to instantly (in the squad leader's command bar order).

^ Might help when someone has a less good Internet connection, dunno.

[ampersand38]

Oh interesting, so each one can run "in parallel"?
As for network, I tried to structure the CBA event and the function such that the selected array is pre-filtered and then only sent on network once, if I'm getting your meaning correctly.