Add serve and start script

package.json

@@ -28,6 +28,7 @@
     "react-responsive-mixin": "^0.4.0",
     "react-reveal": "^1.2.2",
     "react-typed": "^1.0.9",
+    "serve": "^10.0.0",
     "slideout": "^1.0.1",
     "tiny-slider": "^2.8.5",
     "tiny-slider-react": "0.3.4",
@@ -48,7 +49,8 @@
     "develop": "npm run build:css && gatsby develop",
     "develop:cleanstyles": "npm run build:css && purgecss -c ./purgecss.config.js -o ./src/styles && gatsby develop",
     "format": "prettier --write 'src/**/*.js'",
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "start": "serve public/"
   },
   "devDependencies": {
     "prettier": "^1.12.0",