Deletes a failing test without an assert.
Adds testing dependencies and switches to HTTPS for rubygems.
Replaces rspec with minitest.

I've been using minitest for rstat.us and other gems, so it seems
fitting to simply share the infrastructure.

Also, the guy that created rspec completely dismissed me and my friends
on issues I find important:
https://twitter.com/srbaker/status/308682520164179968

So, yeah. Why not get rid of that dependency. :)
Update travis to use new rubies.
Merge pull request #13 from hotsh/feature/minitest

Feature/minitest