2.3.16 Including fix for CVE-2013-0155

In response to this announcement: https://groups.google.com/group/rubyonrails-security/browse_thread/thread/73b8d3f8478df5e2

It's hard to tell whether or not the fix is legitimate:

* There's no updated gem (for 2.3)
* The commit doesn't exist on GitHub
* There's no tag
* The vulnerability is not addressed on the blog
* There's no test
* The code fix looks... strange
* The email is not signed

If this problem is legitimate, and the patch fixes it, we would immensely appreciate an updated Rails 2 gem. Especially since last week's issue in fact did result in a new 2.3 gem.

This PR makes all the necessary preparations, all you need to do is build and push.