Add support for OpenSUSE

I've tested this by running it on my machine, but I'm not sure if the specs are right - `rake spec` fails with

    /usr/bin/ruby1.9 -S rspec spec/classes/java_spec.rb --color
    /usr/bin/ruby1.9: No such file or directory -- rspec (LoadError)
    rake aborted!
    /usr/bin/ruby1.9 -S rspec spec/classes/java_spec.rb --color failed