Updates to 1.9.3, clarifications for Portland Code School

Oisin,

I found your article and your slides and I really like them. I'm going to present them to my students but I wanted to get the code to a place that's a little closer to what they've seen so far. Little things like using File.dirname(__FILE__) instead of Dir.pwd (which I agree is better, they just haven't seen it yet and I want them to stumble on sinatra things instead). 

I also did some general updates. It uses MiniTest and JSON from ruby 1.9.3 and uses a Gemfile now. In addition, I implemented Timecop so the test suite doesn't need to rely on sleep anymore. 

Thanks for getting me started. Whether you pull or not I'm just glad that you were willing to open source this little project! 

Sincerely,
Chuck Lauer Vose
Portland Code School
www.portlandcodeschool.com
@pdxcodeschool