Add ruby class methods

Ruby parser and ruby level for #24

lib/ruby/class_method_statement.rb

@@ -0,0 +1,14 @@
+module Ruby
+  class ClassMethodStatement < MethodStatement
+
+    def to_vool
+#      Vool::ClassMethodStatement.new( @name , @args.dup , @body.to_vool)
+    end
+
+    def to_s(depth = 0)
+      arg_str = @args.collect{|a| a.to_s}.join(', ')
+      at_depth(depth , "def self.#{name}(#{arg_str})" , @body.to_s(depth + 1) , "end")
+    end
+
+  end
+end