Update cluster-controller.rb

fix syntax error on File.open
Update node-controller.rb

fix syntax error at File.open()
Update storage-controller.rb

fix syntax error at File.open()
Update storage-controller.rb

fix syntax error at File.open() part 2
Update walrus.rb

fix syntax error at File.open()
Merge pull request #4 from jerryu/master

quick fix for syntax error at File.open() for four ruby programs.