Use pihole module to get data

[fabaff]

Description:

• Use third-party module to get the data
• Add new condition

Pull request in home-assistant.github.io with documentation (if applicable): home-assistant/home-assistant.io#5492

Example entry for configuration.yaml (if applicable):

sensor:
  - platform: pi_hole
    host: 192.168.0.215

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

If the code communicates with devices, web services, or third-party tools:

• New dependencies have been added to the REQUIREMENTS variable (example).
• New dependencies are only imported inside functions that use them (example).
• New or updated dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.