fix(vehicles): use zones instead of targets

[mafewtm]

Description

• Switches to the use of zones for vehicle spawning as it makes more sense and works better
• Use numeric for loops as we are iterating over arrays
• Send vehicle table instead of just the model so we can add the ability for vehicle customization by config

Same as the qbx_police PR

Checklist

• I have personally loaded this code into an updated Qbox project and checked all of its functionality.
• My pull request fits the contribution guidelines & code conventions.

[Manason]

Change the minimum core version if using new groups API