install_package "yaml-0.1.4" "http://pyyaml.org/download/libyaml/yaml-0.1.4.tar.gz#36c852831d02cf90508c29852361d01b"
install_package "ruby-1.9.3-p392" "http://cache.ruby-lang.org/pub/ruby/1.9/ruby-1.9.3-p392.tar.gz#f689a7b61379f83cbbed3c7077d83859"