Add YAML config stats

[metbril]

Add some statistics sensors for my config:

• number of config lines
• counts of entities in domains

Lines:
https://github.com/pinkywafer/Home-Assistant_Config/blob/master/packages/system/lines.yaml
https://github.com/BeardedTinker/Home-Assistant_Config/blob/master/entities/sensors/system/count_lines.yaml

Counting entities:
https://github.com/BeardedTinker/Home-Assistant_Config/tree/master/entities/sensors/system

[metbril]

Lines: 4fdf1b4

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.