Get all webhooks

Example response

{
  "webhooks": [
    {
      "url": "http://requestb.in/173lyyx1",
      "id": 654,
      "description": "Webhook triggered on campaign openings",
      "events": [
        "opens,clicks"
      ],
      "type": "marketing",
      "createdAt": "2016-12-01T12:50:00Z",
      "modifiedAt": "2017-05-12T13:15:00Z",
      "batched": true,
      "auth": {
        "type": "bearer",
        "token": "test-auth-token1234"
      },
      "headers": [
        {
          "key": "cf-secret",
          "value": "test-header-value"
        }
      ]
    }
  ]
}