Remove #path method from Object

Hi,

I had some trouble parsing a YAML file when running in JRuby. It turns out that Object responded to `#path`, which messed up the JRuby Psych parser. I tracked the problem down to the `path` method defined in this gem. You probably didn't intend for every object to now have a `path` method. =)

I fixed things up so there's no `path` method defined on Object now.

Thanks again for creating the gem!