Add an option to hide gear and speed about ac-traces

[frits-z]

Hi Kishlin!

Thanks for your message and kind review on RaceDepartment. First time I've got a comment on github 😀

I am currently not actively maintaining the app anymore, as I haven't played Assetto Corsa in a good while, I would need to reinstall it even!

I think adding this option should be relatively easy. We'd need a config option, an alternative background .png file, and some small tweaks to the code to stop those elements from loading & drawing based on the config flag.

If you want to give it a try and make a pull request, feel free! Else, I might take a look at it myself when I have the time, but no idea on when that might be.

Cheers!