Add spec for Warning.warn
Add spec for Warning.warn

sgarciac/spec,eregon/rubyspec,ruby/rubyspec,eregon/rubyspec,sgarciac/spec,sgarciac/spec,ruby/spec,nobu/rubyspec,eregon/rubyspec,ruby/spec,ruby/spec,ruby/rubyspec,nobu/rubyspec,nobu/rubyspec