Fix issue #16

Here's a quick fix for issue #16, it was a bug similar to the one we had with turbolinks. The regular expression for parsing version numbers wasn't exclusive enough, so it parsed the number in gem's name as a version number.

I have to leave town in a couple of minutes so I can't test it manually, but both the new test and all the previous tests are passing normally, so everything should be fine.

Nice catch, and if you find any issues with this pull request, let me know and I can fix them up tomorrow when I come back home.

Cheers. :beers: