Instead of `detective`, this way we will be able to support
`tailwind.config.ts` files and `ESM` files.

TODO: Test all combinations of `--full`, `--ts`, `--postcss`, and `--esm`.

Did you know you could pass an empty args to a command? No? Me neither. ¯\_(ツ)_/¯

We are not displaying output in the `--help` anymore based on whether
`type: module` is present or not.
Therefore this test is unneeded.

…s well

This will allow you to use:

```js
import loadConfig from 'tailwindcss/loadConfig'

let config = loadConfig("/Users/xyz/projects/my-app/tailwind.config.ts")
```

The `loadConfig` function will return the configuration object based on
the given absolute path of a tailwind configuration file.

The given path can be a CJS, an ESM or a TS file.

…file

The root `defaultConfig` is still there for backwards compatibilty
reasons. But the `module.exports = requrie('./config.full.js')` was
causing some problems when actually using tailwindcss.

So dropped it instead.

A little smaller but just for tests so doesn't matter too much here 👍