Add `triggerEvent`

[jbuchacher]

Adds basic support for triggering events in API.ai.

Use cases

Conditional API.ai intent routing via logic in Botpress

bp.hear({'nlp.action': 'some-action-name'}, (event, next) => {
  const someParameter = event.nlp.parameters.SomeParameter
  if (someParameter === someCondition) {
    event.nlp.triggerEvent("some-other-event")
  } else {    
    event.reply('#otherResponse')
  }
})

Proactive messaging

someOtherSystem.on('some_event', () => {
  event.nlp.triggerEvent("some-other-event", { someData: '' } )
})

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[slvnperron]

Hi Joshua, thanks for your contribution. I just wanted to hear more about the use case behind this feature?

[jbuchacher]

@slvnperron I'm using Dialogflow prompts and context quite a bit. When a user is halfway through an intent that has a bunch of prompts, and they answer a question, I can trigger a Dialogflow event and immediately get back fulfillment information for the other intent, instead of adding context and then requiring the user to say something to actually trigger the other intent.