* Add failing tests for negative utility detection
We're not generating them properly in all cases, when using at-apply we sometimes crash, and safelisting doesn't currently work as expected.
* Refactor
* Generate utilities for negatives before and after the prefix
* Properly detect negative utilities with prefixes in the safelist
* Refactor test a bit
* Add class list tests
* Update changelog
* move `./tests/jit` to `./tests`
* make tests consistent
Abstracted a `run` function and some syntax highlighting helpers for
`html`, `css` and `javascript`.