anchor.diff:          .success(function(data){
             update_current_game_id(data.id);
             update_score();
  -          update_error_message("");
  +          clear_error_message();
             console.log("Success on requesting POST '/games'. Created game with id: " + data.id);
           })
           .error(function(data){
  
positive.code: 
      function send_knocked_pins(knocked_pins){
        $.ajax({
          "url": "/games/"+current_game_id,
          "type": "PUT",
          "data": {"knocked_pins": knocked_pins}
        })
          .success(function(){
            update_score();
            update_error_message("");
            console.log("Success on requesting PUT '/games/" + current_game_id + " with body: {knocked_pins: " + knocked_pins + "}");
            $("#knocked-pins").val("");
          })
          .error(function(data){
            update_error_message(data.responseJSON.message);
            console.error("Error on requesting PUT '/games/" + current_game_id + " with body: {knocked_pins: " + knocked_pins + "}");
            console.error(data);
          })
      }
  
      function update_error_message(message){
        $("#error-message").text(message);
      }
    })
  </script>
  
negative.code:         .success(function(data){
            console.log("Success on requesting GET '/games/" + current_game_id);
            $("#game-score").text(data.score);
            $("#game-frames").text(data.frame_number);
            $("#game-over").text(data.game_over.toString());
          })
          .error(function(data){
            console.error("Error on requesting GET '/games/" + current_game_id);
  