Need to add the Ford Mustang

[MMsicarius]

Hello there

Could you add any missing content that hasn't been added. I noticed the mustang was missing but idk if there are any tracks missing as well.

[Stoolbend]

I've added the missing cars & tracks to the new version, but have just realised I haven't made an event.json editor yet 🙃.
I'll try and get one made soon so that you can access the new tracks on https://acctoolkit-next.bigc.industries/.