move vool statements into own directory

also tests for guard to work

lib/vool/statements/send_statement.rb

@@ -0,0 +1,9 @@
+module Vool
+  class SendStatement < Statement
+    attr_reader :name , :receiver , :arguments
+
+    def initialize(name , receiver , arguments = [])
+      @name , @receiver , @arguments = name , receiver , arguments
+    end
+  end
+end