Use JSON for config files

Towards getting rid of CommonJS

.eslintrc.js

-module.exports = {
-  env: {
-    browser: true,
-    es6: true,
-    node: true,
-    jest: true,
-  },
-  extends: "eslint:recommended",
-  globals: {
-    Atomics: "readonly",
-    SharedArrayBuffer: "readonly",
-  },
-  parserOptions: {
-    ecmaVersion: 2018,
-    sourceType: "module",
-  },
-  rules: {},
-}

.eslintrc.json

+{
+  "env": {
+    "browser": true,
+    "es6": true,
+    "node": true,
+    "jest": true
+  },
+  "extends": "eslint:recommended",
+  "globals": {
+    "Atomics": "readonly",
+    "SharedArrayBuffer": "readonly"
+  },
+  "parserOptions": {
+    "ecmaVersion": 2018,
+    "sourceType": "module"
+  },
+  "rules": {}
+}

.prettierrc.js

-module.exports = {
-  semi: false,
-  printWidth: 80,
-  tabWidth: 2,
-  useTabs: false,
-  singleQuote: false,
-  trailingComma: "all",
-  arrowParens: "always",
-  endOfLine: "lf",
-}

.prettierrc.json

+{
+  "semi": false,
+  "printWidth": 80,
+  "tabWidth": 2,
+  "useTabs": false,
+  "singleQuote": false,
+  "trailingComma": "all",
+  "arrowParens": "always",
+  "endOfLine": "lf"
+}