chore: Add lint-staged for prettier

Author: relekang

package.json

@@ -16,6 +16,7 @@
     "node": ">=6.0.0"
   },
   "scripts": {
+    "precommit": "lint-staged",
     "start": "./cli.js",
     "now-build": "npm install micro-analytics-adapter-memory",
     "now-start": "node src/index.js --adapter memory",
@@ -32,6 +33,9 @@
       "src/**/*.js"
     ]
   },
+  "lint-staged": {
+    "*.js": ["prettier --single-quote --trailing-comma es5 --write", "git add"]
+  },
   "author": "Max Stoiber <[email protected]> (http://mxstbr.com/)",
   "license": "MIT",
   "repository": "https://github.com/mxstbr/micro-analytics",
@@ -52,7 +56,9 @@
     "babel-plugin-transform-async-to-generator": "^6.16.0",
     "babel-polyfill": "^6.20.0",
     "babel-preset-node6": "^11.0.0",
+    "husky": "^0.13.4",
     "jest": "^19.0.2",
+    "lint-staged": "^3.5.0",
     "micro-analytics-adapter-memory": "^0.1.0",
     "nodemon": "^1.11.0",
     "prettier": "^1.3.1",