First argument fix

Author: snehitgajjar

spec/fixtures/group.thor

@@ -9,7 +9,7 @@ class MyCounter < Thor::Group
   source_root File.expand_path(File.dirname(__FILE__))
   source_paths << File.expand_path("broken", File.dirname(__FILE__))
 
-  # argument :first,       :type => :numeric
+  argument :first,       :type => :numeric
   argument :second,      :type => :numeric, :default => 2
 
   class_option :third,    :type => :numeric, :desc => "The third argument", :default => 3,