While doing this, also update the configuration section to current
configuration markup best practices, which also fixed a number of
inaccuracies with the defaults by cross checking with the source code.
Fixes issue home-assistant/home-assistant#11821
* Update device_tracker.unifi.markdown
For
https://github.com/home-assistant/home-assistant/pull/8998
* Update device_tracker.unifi.markdown
* Update device_tracker.unifi.markdown
* Update device_tracker.unifi.markdown
* Removed API configuration parameter from the documentation
* Some minor spelling & grammar fixes
Add site_id description to the page. This configuration detail allows you to specify which site is surveyed for devices. Useful if the controller has multiple sites.