Add eslint

Author: albertfdp

.eslintrc.js

@@ -0,0 +1,19 @@
+module.exports = {
+  extends: "eslint:recommended",
+
+  plugins: ["jest"],
+
+  parserOptions: {
+    ecmaVersion: 12,
+  },
+
+  env: {
+    browser: true,
+    commonjs: true,
+    es2021: true,
+    node: true,
+    "jest/globals": true,
+  },
+
+  rules: {},
+};

.prettierrc

@@ -0,0 +1,3 @@
+{
+  "singleQuote": false
+}