Merge pull request #478 from cal-smith/storybook-postcss

chore(storybook): add postcss loader

Author: zvonimirfras

.storybook/config.js

@@ -27,8 +27,8 @@ addDecorator(
 );
 
 // load global styles
-require("!style-loader!css-loader!sass-loader!./preview.scss");
-require("!style-loader!css-loader!sass-loader!./preview-experimental.scss");
+require("!style-loader!css-loader!postcss-loader!sass-loader!./preview.scss");
+require("!style-loader!css-loader!postcss-loader!sass-loader!./preview-experimental.scss");
 
 require("../src/index.stories");
 // automatically import all files ending in *.stories.ts