refactor: Use ES6 classes instead of createClass

package.json

@@ -27,6 +27,7 @@
   "dependencies": {
     "babel-cli": "^6.4.0",
     "babel-eslint": "^7.2.1",
+    "babel-plugin-transform-class-properties": "^6.24.1",
     "babel-polyfill": "^6.3.14",
     "babel-preset-es2015": "^6.3.13",
     "babel-preset-react": "^6.3.13",
@@ -44,9 +45,9 @@
     "isomorphic-fetch": "^2.2.0",
     "lodash.debounce": "^4.0.3",
     "minifyify": "^7.1.0",
+    "prop-types": "^15.5.9",
     "react": "^15.0.2",
     "react-dom": "^15.0.2",
-    "react-pure-render": "^1.0.2",
     "remark": "^7.0.0",
     "remark-html": "^6.0.0",
     "remark-slug": "^4.1.0",