First, get ruby 1.9.2+ installed on your machine. I would suggest you do this / manage the installation by way of rvm.
Once that's done, when you cd into the directory for the project it should create the gemset for you. Then install the required libraries by:
gem install bundler
bundle
Once that's done, you should be able to run the tests.
bundle exec rake test
You should see them all pass. It's working on your system at this point.
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