Audit dependencies

[pdehaan]

Just a quick check. I think everything looks OK to my aging eyes, but worth a second look with somebody that has more than 20 minutes of experience with this repo:

$ npx depcheck

Unused dependencies
* json-url

Unused devDependencies
* babel-core
* babel-loader
* babel-plugin-transform-object-rest-spread
* babel-preset-env
* babel-preset-node8
* babel-preset-react
* clean-webpack-plugin
* css-loader
* eclint
* ejs
* eslint-config-airbnb-base
* eslint-plugin-import
* eslint-plugin-react
* image-webpack-loader
* node-sass
* sass-loader
* style-loader
* svg-url-loader
* url-loader

json-url felt fishy, but looks like we're manually copying the file from ./node_modules/ into a /vendor/ directory (which is cool).

Babel and ESLint and *-loader results are always fishy, based on how they are loaded by their respective tools.

So I think maybe the only one that strikes me was eclint. I didn't see any errors when running npx eclint . locally, so I'm guessing there were no editorconfig errors. Not sure if we want to create some npm task which calls eclint or not. We could potentially extend npm run lint to run ESLint and eclint (and some Sass linter if we feel under-linted).

blah blah blah

---

$ npx depcheck --ignores=*-loader,eslint-*,babel-*

Unused dependencies
* json-url

Unused devDependencies
* clean-webpack-plugin
* ejs
* node-sass

[lmorchard]

Look like sass-loader depends on node-sass, despite what depcheck says. Build fails if I omit it from dependencies. The other two - clean-webpack-plugin and ejs - were used in code that I've since deleted, so they can go for now