💥[BREAKING] 💥 Commonjs, module build enhancements

[petermikitsh]

💥BREAKING CHANGES 💥

For versions 1.2.1 (inclusive) and prior, the distributions were kind of incorrect.

• The commonjs dist/index.js file had module ES module import/export syntax.
• The commonjs source files had their css inlined (poor for performance and causes bundle size bloat).
• The module build couldn't be tree-shaken since {sideEffects: false} was not set in package.json.
• Both builds missed other opportunities for reducing bundle size, like removing prop types.

This PR addresses all of these things.

• In both builds, you'll need handle css files. With webpack, use css-loader to handle the CSS files. For a babel-only solution, use babel-plugin-css-modules-transform.
• If applicable, you'll need to handle the svg files imported as well. Something like babel-plugin-inline-react-svg should do. For webpack, use react-svg-loader.