chore(docs): list minimum node as 4 (#2547)

Author: filipesilva

public/docs/ts/latest/quickstart.jade

@@ -59,7 +59,7 @@ h1 Prerequisite: Install #{_prereq}
 block setup-tooling
   :marked
     If Node.js and npm aren't already on your machine, <a href="http://blog.npmjs.org/post/85484771375/how-to-install-npm"
-    target="_blank">install them</a>. Our examples require node **v5.x.x** or higher and
+    target="_blank">install them</a>. Our examples require node **v4.x.x** or higher and
     npm **3.x.x** or higher. To check which version you are using, run `node -v` and `npm -v`
     in a terminal window.