Glances Docker Sensors

[timmo001]

Description:

Added three new sensors from Docker object in API. Shows total active containers, total CPU use and total memory use

Pull request in home-assistant.github.io with documentation (if applicable):
home-assistant/home-assistant.io#4873

Example entry for configuration.yaml (if applicable):

sensor:
  - platform: glances
    host: IP_ADDRESS
    resources:
      - 'disk_use_percent'
      - 'disk_use'
      - 'disk_free'
      - 'memory_use_percent'
      - 'memory_use'
      - 'memory_free'
      - 'swap_use_percent'
      - 'swap_use'
      - 'swap_free'
      - 'processor_load'
      - 'process_running'
      - 'process_total'
      - 'process_thread'
      - 'process_sleeping'
      - 'cpu_temp'
      - 'docker_active'
      - 'docker_cpu_use'
      - 'docker_memory_use'

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in home-assistant.github.io

[fabaff]

Thanks 🐦