int.random behaviour

```gleam
pub fn random(min: Int, max: Int) -> Int
```

1. "min" and "max" can be used interchangeably, which is confusing to me. e.g. random(-1, 1) is the same as random(1, -1)
2. the maximum value is excluded from output (i.e. not the `max` but the actually higher value)

I'm not sure if this behaviour is intended, but at least it needs to be documented.