[WIP] Support GraphQL endpoint

[deric]

Here' s a draft of API v2 support. Currently supports read-only queries. There will be definitely breaking changes (at least in authentication). When using GraphQL API we might add support for multiple controllers.

Example usage:

from hydrawiser.graphql import HydrawiserV2

hw = HydrawiserV2('<your email>', '<your hydrawise password>')
hw.controllers()

customer():

{
  "id": 123, # controller id
  "customerId": 99999,
  "name": "John Doe ",
  "email": "john@example.com",
  "validated": true,
  "controllers": [
    {
      "id": 11111,
      "name": "Garden",
      "deviceId": 123456
    }
  ]
}

controllers():

[
  {
    "id": 123, # controller id
    "name": "Garden",
    "online": true,
    "deviceId": 777,
    "wizardComplete": true,
    "hardware": {
      "serialNumber": "a3egafe1",
      "version": "hydrawise116",
      "status": "Linked",
      "installationDate": "Fri, 16 Jul 21 17:34:11 +0000"
    },
    "softwareVersion": "6.26",
    "boc": false,
    "lastAction": {
      "value": "Fri, 01 Apr 22 11:26:44 +0200",
      "timestamp": 1648805204
    }
  }
]

sensors():

[
  {
    "id": 123, # controller id
    "name": "Garden",
    "sensors": [
      {
        "id": 789456,
        "name": "Rainfall",
        "model": {
          "id": 4444,
          "name": "Rain Sensor (normally closed wire)",
          "modeType": "STOP",
          "active": true,
          "offLevel": 1,
          "offTimer": 0,
          "delay": 0,
          "divisor": 0,
          "flowRate": 0,
          "customerId": 0,
          "sensorType": "LEVEL_CLOSED",
          "category": {
            "name": "Hunter Clik"
          }
        }
      }
    ]
  }
]

zones():

[
  {
    "id": 123,
    "name": "Garden",
    "zones": [
      {
        "id": 100,
        "name": "Zone 1"
      },
      {
        "id": 101,
        "name": "Zone 2"
      }
    ]
  }
]

TODO:

• Schedule running a zone
• Suspend zone/relay
• Retrieve sensor status
• Update monitored attributes
• Refresh OAuth2 token

This PR adds dependency on gql library, which seems to be a minimalistic GraphQL client, but Python 2 is no longer supported.

@ptcryan Is it ok to continue with implementation this way? The responses should be Python dict or JSON is preferred?