remove bundler version dependencies

[nelliemckesson]

@mattretzer I think we should remove the version dependencies in bundler whenever possible. It causes bookmaker to crash if any gem versions are out of date, which is bad. But I'm open to other arguments.

[mattretzer]

Wow, I don't think that's supposed to happen :(
Let me know if you want me to change this today or if we can wait and discuss Thursday?

[nelliemckesson]

Let's discuss Thursday. FYI this was when I was running it on my local machine, which comes with some extra issues, so presumably it wouldn't crash on the server versions.

[stefanv]

I've run into this issue as well. It may be worth reviewing the README installation instructions as well; they don't work unmodified (at least, not on a modern OSX brew system). E.g., note:

• Current dependencies cannot be installed under Ruby 1.9 (the version advocated)
• Dependencies can be installed as follows (I'm not a Ruby user, so I don't know if this is the best way):

gem install bundler
bundler install