Commonjs no css require

[petermikitsh]

Since the ES5 version is actually pretty useful for server-side rendering, I want it to be friendly to Node-based environments. That being said, requiring css files breaks node. So, let's take 'em out.

Individual CSS files are still included in the dist folder. Consumers in ES5 environments can decide themselves how to make use of them.

Example (dist/AppBar/AppBar.js):

Before:

require("./AppBar.css");

var Styles = {
  "root": "AppBar-root",
  "header": "AppBar-header",
  ...
};

After:

// no require statement

var Styles = {
  "root": "AppBar-root",
  "header": "AppBar-header",
  ...
};