Allows devs to overwrite quark props to use their own functions

[dslovinsky]

Changes

• Creates getConfig to load the contents of user quarks.config.ts
• Allows devs to overwrite quark props to use their own functions

Closes #9

Other notes (things to check, explanation of implementation, etc.)

The challenge here has been loading the config in a method that a frontend framework like next supports. The problem is next seems to not like that fs is being used within findup-sync since this is a frontend project where fs is not allowed. But it's the only way we have access to the dependent repo's config file.
Relevant threads:

1. https://stackoverflow.com/q/69216029
2. https://stackoverflow.com/q/56729491

Why use findup-sync:
Ordinarily we could just use path.resolve to get the contents of a specific file path in the dependent project, but the difficult is that "root directory" can actually mean several different places, for example depending on if you're in a monorepo. So instead the approach is to start from a working directory then move up into ancestors looking for a file that matches the target glob. Findup sync seems good for this:

Example:
See lib/loadConfig.ts in Tailwind

JITI may useful:
https://www.npmjs.com/package/jiti

[jpwallace22]

@dslovinsky I didnt see any use of findup-sync or fs in the Tailwind library. Also, after digging into it a bit, I notice that this package hasn't been touched in two years and never had great support to begin with. Are we sure that there isn't anything wrong with findup-sync? We can write a custom function to search for the config file pretty easily.