For the current setup where people have to fork or at least clone quartz
this changes nothing - but it allows you to install quartz as a
devDependency via npm and have it actually work.
One real change is switch from `.quartz-cache` to
`node_modules/.cache/quartz` for transpilation results, this is an
artifact from my previous attempts, I guess with this one I can change
it back - but `node_modules/.cache` feels more better imo idk.
edit: OTOH if you want to have quartz be a _completely_ separate binary
(which this also enables I think), having it create a node_modules
folder is weird, so I made a quick hack for that for now.
Example:
```bash
$ mkdir my-repo && cd my-repo
$ npm i quartz@necauqua/quartz#untangled # quartz@ prefix is important
$ cp node_modules/quartz/quartz.*.ts . # copy the default configs
$ mkdir content && echo "# Hello World!" > content/index.md
$ npx quartz build --serve # this just works!
$ echo 'body { background: red !important; }' > styles.scss
```
Notice how I used my branch in the `npm i` line, ideally it'd be
`npm i quartz@jackyzho0/quartz`, or maybe we can somehow get the quartz
package on npm and it'll just be `npm i quartz`.
In the latter case `npx quartz build` will literally just work without
a local npm package at all?.
Having some support for components and plugins being in separate npm
packages instead of people copying code around is not out of the picture
with this too btw.
Closes#502
MOVE ME
