Add prettier husky and lint-staged

package.json

@@ -22,13 +22,16 @@
     "babel-loader": "^8.1.0",
     "chai": "^4.2.0",
     "cross-env": "^5.2.0",
+    "husky": "^4.3.8",
     "karma": "^3.1.1",
     "karma-chai": "^0.1.0",
-    "karma-mocha": "^1.2.0",
     "karma-chrome-launcher": "^2.2.0",
+    "karma-mocha": "^1.2.0",
     "karma-sinon": "^1.0.4",
     "karma-webpack": "^3.0.5",
+    "lint-staged": "^10.5.3",
     "mocha": "^5.2.0",
+    "prettier": "2.2.1",
     "sinon": "^7.1.1",
     "uglifyjs-webpack-plugin": "^2.0.1",
     "webpack": "^4.5.0",
@@ -41,5 +44,13 @@
     "build-watch": "webpack --watch",
     "test": "karma start --single-run",
     "prepublish": "npm run build"
+  },
+  "husky": {
+    "hooks": {
+      "pre-commit": "lint-staged"
+    }
+  },
+  "lint-staged": {
+    "*.{js,css,md}": "prettier --write"
   }
 }