Adds test coverage for number_handler [WORK IN PROGRESS]

## WORK IN PROGRESS: Please do not merge!

Hi Gavin:

I saw that you guys are hiring on through 37Signals job board. This pull request is my way of showing that we're interested.

This is still a work in progress, but you can sneak a peek before it's done. I'll send an email to you and the rest of the team with full details once this is ready to go. By that time, this message will be changed to better reflect the efforts here.

We're a small team of experts in Quakertown, PA. I believe that working with us can lead to a higher quality of code for you and your team because of the collaborative, team-based approach we take to our work. Everything we do is test backed, developed in feature branches, and peer-reviewed before being merged to master.

I'm submitting this in the hopes that you'll see the business value of testing your shared code and get a sneak preview of just how awesome Real HQ could be if Reenhanced is on your side.

That's enough for now. If you're interest in a sneak peek, please take a look at what's been done here. It still needs to be completed and put through our code review process before its ready for a full submission, so please don't merge this down. It isn't ready for release.

I hope all is going well. I'll talk to you more tomorrow.

Nick
CEO
Reenhanced, LLC

http://www.reenhanced.com/