Add watched_lights config option

[th3w1zard1]

Closes #451 Requires #512

Adds the following config option:
watched_lights

Documentation:
Use this dictionary of lights to check for manually controlled events in addition to the main lights 🌟 Example: {light.watch_light: light.main_light} will fire manually controlled events to light.main_light

Default:
{}

Type:
dictionary of entity_ids pointing to the main lights they reference

[th3w1zard1]

Good to know test_state_change_handlers works. Will fix later.

[th3w1zard1]

Exact test actually fails in alt_detect_method

[th3w1zard1]

fixed - it now passes