def tokens(cmd, text)
      valide_command!(cmd)
      Enumerator.new do |yielder|
        call(cmd, text).each do |freeling_line|
          yielder << parse_token_line(freeling_line) unless freeling_line.empty?
        end
      end
    end
def tokens(cmd, text)
      valide_command!(cmd)
      Enumerator.new do |yielder|
        call(cmd, text).each do |freeling_line|
          yielder << parse_token_line(freeling_line) unless freeling_line.empty?
        end
      end
    end
Generate tokens for a given text

 Example:

   >> analyzer = FreelingClient::Analyzer.new
   >> analyzer.token(:morfo, "Este texto está en español.")

 Arguments:
   cmd: (Symbol)
   text: (String)