via https://css-tricks.com/learning-gutenberg-7-building-our-block-custom-card-block/
other good tutorial: http://jschof.com/gutenberg-blocks/wordpress-gutenberg-blocks-example-creating-a-hero-image-block-with-inspector-controls-color-palette-and-media-upload-part-1/
cd ../../../../../Applications/MAMP/htdocs/brandv2wp5/wp-content/plugins
ls
mkdir card-block
cd card-block/
touch card-block.php
npm init
npm install webpack --save-dev
npm install extract-text-webpack-plugin@next --save-dev
npm install node-sass sass-loader css-loader --save-dev
npm install npx -g
npm install webpack-cli --save-dev
touch webpack.config.js
npm install @babel/core babel-loader babel-plugin-add-module-exports babel-plugin-transform-react-jsx @babel/preset-env --save-dev
touch .babelrc
mkdir blocks
cd blocks
mkdir src
mkdir dist
cd src
touch blocks.js
touch common.scss
mkdir block
cd block
touch block.js
touch editor.scss
touch style.scss
cd ../..
cd ..
ls
npx webpack
npx webpack --watch