Custom controller button mappings

[virtexedge]

As per Steam discussion: https://steamcommunity.com/app/938200/discussions/0/3111394035958037868/

[petedermott]

I'd like to +1 this.

Currently can't use a d-pad to steer which I personally find to be faster than using a stick, especially at high speeds.

Additionally, the current binding of the buttons feels odd to me. I would expect fire to be on a face button rather than opposite of accelerate and I find it a little cumbersome to use air breaks and accelerate at the same time.