Working NPM installable version with GitHub Action publish

[0xFlicker]

Adds a working installable variation w/ GitHub Actions publish.

Used to create https://www.npmjs.com/package/operator-filter-registry

I pushed and this created this package name w/o much forethought, hit me up on Twitter or in the OpenSea discord if you want to coordinate handing it over. In any case, all I wanted was to be able to npm import the smart contracts like how I import everything else.

The only weird thing I needed to do was to find-and-replace the imports for openzeppelin contracts to match what is used on NPM.

Tested and works for me.