presets for common use cases

[FND]

It would be nice if getting started was a simple two-step process:

$ npm install faucet-pipeline faucet-pipeline-js faucet-pipeline-sass
$ faucet --presets=js,sass,manifest --fingerprint

Thus --presets would replace faucet.config.js for common use cases, reducing infrastructure, moving parts, maintenance burden, cognitive load etc.

However, presets would not allow for any customization; if that's required, faucet.config.js should be used.

In the example above, the presets would result in the following configuration:

{
    sass: [{
        source: "./src/index.sass",
        target: "./dist/bundle.css"
    }],
    js: [{
        source: "./src/index.js",
        target: "./dist/bundle.js"
    }],
    manifest: {
        file: "./dist/manifest.json",
        baseURI: 🤔 // not sure how this would work
    }
}