Switch debugging http server from python's http server to a http-server.

package.json

@@ -13,7 +13,7 @@
   },
   "scripts": {
     "dev": "rollup -c rollup.config.dev.js -w",
-    "serve": "python3 -m http.server --bind 127.0.0.1 8888",
+    "serve": "http-server",
     "test": "mocha",
     "lint": "eslint",
     "build": "rollup -c rollup.config.js",
@@ -28,11 +28,12 @@
     "chai": "^3.5.0",
     "eslint": "^4.3.0",
     "eslint-config-google": "^0.9.1",
+    "http-server": "^0.11.1",
     "js-yaml": "^3.7.0",
     "jsdom": "11.3.0",
     "jsdom-global": "3.0.2",
-    "marked": "^0.3.6",
-    "mocha": "^3.5.3",
+    "marked": "^0.6.0",
+    "mocha": "^5.2.0",
     "prismjs": "^1.6.0",
     "rollup": "^0.50.0",
     "rollup-plugin-babili": "^3.1.0",