chore: upgrade webpack and dev server

.babelrc.js

@@ -8,9 +8,7 @@ const plugins = [
 ].filter(Boolean);
 
 const presets = [
-  [
-    '@babel/preset-env', { useBuiltIns: 'entry' }
-  ],
+  ['@babel/preset-env', { useBuiltIns: 'usage', corejs: { version: 3 } }],
   [
     '@babel/preset-react',
     {

.eslintrc

@@ -22,14 +22,14 @@
     },
     "import/resolver": {
       "webpack": {
-        "config": "config/dev.js"
+        "config": "config/webpack.config.dev.js"
       }
     }
   },
   "rules": {
     "id-length": [
       2,
-      { "min": 3, "max": 30, "properties": "never", "exceptions": ["_", "cb"] }
+      { "min": 2, "max": 30, "properties": "never", "exceptions": ["_", "cb"] }
     ],
     "max-params": [2, 3],
     "no-cond-assign": [2, "except-parens"],

config/paths.js

@@ -0,0 +1,20 @@
+const path = require('path');
+const fs = require('fs');
+
+// Make sure any symlinks in the project folder are resolved:
+// https://github.com/facebookincubator/create-react-app/issues/637
+const appDirectory = fs.realpathSync(process.cwd());
+const resolveApp = relativePath => path.resolve(appDirectory, relativePath);
+
+module.exports = {
+  appBuild: resolveApp('dist'),
+  appDist: resolveApp('dist'),
+  appPublic: resolveApp('docs'),
+  appHtml: resolveApp('docs/index.html'),
+  appIndexJs: resolveApp('docs'),
+  appDistJs: resolveApp('src/index.js'),
+  appPackageJson: resolveApp('package.json'),
+  appDemo: resolveApp('docs'),
+  appSrc: resolveApp('src'),
+  appNodeModules: resolveApp('node_modules'),
+};

config/postCssConfig.js

@@ -0,0 +1,14 @@
+const autoprefixer = require('autoprefixer');
+const flexBugFixes = require('postcss-flexbugs-fixes');
+
+module.exports = {
+  // Necessary for external CSS imports to work
+  // https://github.com/facebookincubator/create-react-app/issues/2677
+  ident: 'postcss',
+  plugins: () => [
+    flexBugFixes,
+    autoprefixer({
+      flexbox: 'no-2009',
+    }),
+  ],
+};