#15 add support for template tag to Facebook for botkit

[jsalwen]

#15 add support for template tag to Facebook for botkit

• add dashbotTemplateId in botkitTransformOutgoing
• add addTemplateTag method
• update example on usage

Calling addTemplateTag will queue up a template tag to be added to the next message logged to Dashbot

[jsalwen]

@jhullfly I tried adding the dashbotTemplateId to botkit message object, but all non-facebook properties are stripped out.

If you have a better approach, let me know, and I will update PR and test.

[techno246]

@jsalwen My approach was to add the dashbotTemplateId in the message object, and in the botkitTransformOutgoing(bot, message) method, use the getAndRemove method like for the channel object. Seems to work well.

  function botkitTransformOutgoing(bot, message) {
    var sendMessage = _.cloneDeep(message);
    var channel = getAndRemove(sendMessage, 'channel');
    var templateTagId = getAndRemove(sendMessage, 'dashbotTemplateId');
    return {
      qs: {
        access_token: bot.botkit.config.access_token
      },
      json: {
        dashbotTemplateId: templateTagId,
        recipient: {
          id: channel
        },
        message: sendMessage
      }
    };
  }