Update build process and move to checkJs

Author: developit

package.json

@@ -2,10 +2,10 @@
   "name": "task-worklet",
   "version": "0.1.0",
   "description": "Streamlined processing of tasks in a shared threadpool.",
-  "source": "src/index.mjs",
+  "source": "src/index.js",
   "main": "dist/task-worklet.js",
   "umd:main": "dist/task-worklet.js",
-  "module": "dist/task-worklet.mjs",
+  "module": "dist/task-worklet.module.js",
   "scripts": {
     "build": "microbundle -f umd,es && microbundle -f iife src/polyfill.mjs -o polyfill/index.js",
     "test": "eslint \"{src,test}/**/*.test.{mjs,js}\" && karmatic --no-headless"
@@ -16,20 +16,29 @@
     "polyfill.js"
   ],
   "eslintConfig": {
-    "extends": "google",
+    "extends": [
+      "google",
+      "prettier"
+    ],
     "parserOptions": {
       "ecmaVersion": 2018,
       "sourceType": "module"
     },
     "rules": {
       "require-jsdoc": 0,
+      "valid-jsdoc": 0,
       "max-len": 0,
       "guard-for-in": 0,
       "new-cap": 0,
       "prefer-rest-params": 0
     }
   },
-  "repository": "GoogleChromeLabs/task-worklet",
+  "prettier": {
+    "singleQuote": true,
+    "trailingComma": "none",
+    "tabWidth": 2
+  },
+  "repository": "developit/task-worklet",
   "keywords": [
     "tasks",
     "task worklet",
@@ -39,13 +48,15 @@
   ],
   "author": "Jason Miller <developit@google.com>",
   "license": "Apache-2.0",
-  "homepage": "https://github.com/GoogleChromeLabs/task-worklet",
+  "homepage": "https://github.com/developit/task-worklet",
   "devDependencies": {
-    "eslint": "^5.2.0",
-    "eslint-config-google": "^0.9.1",
-    "file-loader": "^2.0.0",
-    "karmatic": "^1.2.0",
-    "microbundle": "^0.9.0",
-    "webpack": "^4.16.4"
+    "eslint": "^7.9.0",
+    "eslint-config-google": "^0.14.0",
+    "eslint-config-prettier": "^6.11.0",
+    "file-loader": "^6.1.0",
+    "karmatic": "^2.1.0",
+    "microbundle": "^0.12.3",
+    "prettier": "^2.1.2",
+    "webpack": "^4.44.1"
   }
 }