Add eslint, prettier, husky and lint-staged

Author: mmarkelov

.eslintignore

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+lib/
+node_modules/

.eslintrc.js

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+module.exports = {
+  root: true,
+  extends: ['airbnb-base', 'prettier'],
+  parser: 'babel-eslint',
+  parserOptions: {
+    ecmaVersion: 2018,
+    sourceType: 'module',
+  },
+  env: {
+    node: true,
+    jest: true,
+    browser: true,
+  },
+  globals: {
+    page: true,
+    browser: true,
+    context: true,
+  },
+}

.prettierignore

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+lib/
+node_modules/

.prettierrc

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+{
+  "singleQuote": true,
+  "trailingComma": "all",
+  "semi": false
+}