Created by: pavinthan
This PR created after discustion about "PostCSS plugins support" in https://spectrum.chat/create-react-app/general/postcss-plugins-support~819b4e89-ea77-4010-86d4-dd82b4fa33e6?m=MTU3NDA5NTgwODc5NA==
Can you raise a PR for adding this in? We would be open to discuss PostCSS plugin support - but not full Webpack support at this stage.
@mrmckeb may you please have a look into this PR?