def url_for params
      p = params.dup
      query = p.map{|key, value| value.to_query(key) } * '&'
      "#{h.url_for({})}?#{query}"
    end
def url_for params
      p = params.dup
      query = p.map{|key, value| value.to_query(key) } * '&'
      "#{h.url_for({})}?#{query}"
    end
dirty hack to avoid rails' sorted query in url