Programmatically create a DialogFlow CS agent in PHP (Proof Of Concept)

The aim of this project is to be able to programmatically create a DialogFlow CS agent in PHP.

Beware: to create a DialogFlow CS agent you need to programmatically:

- create a project in the Google Console
- create a service account linked to the above project
- assign to the service account the required roles (Dialogflow API Admin, Dialogflow API Client, Dialogflow API Reader)
- create and download a JSON key to authenticate as a service account
- create the agent using the previously obtained credentials.

The deliverables must include:

- All the source codes
- A detailed step by step guide on how to create the credentials (i.e. service account) with roles, permissions and so on needed to execute the script.

You can use any library, including Google Cloud's one:

https://googleapis.github.io/google-cloud-php/#/