Use HTTPS and www to avoid costly redirects.

We first redirect any calls to `codeschool.com` to `www.codeschool.com` and then any clear HTTP call to HTTPS. 
You might as well avoid those redirects (and potential 301 hurdles along the way) by using the proper URL.
Merge pull request #1 from olivierlacan/patch-1

Use HTTPS and www to avoid costly redirects.