Reorg auth (#15443)

homeassistant/auth/__init__.py

homeassistant/auth/auth_store.py

homeassistant/auth/const.py

homeassistant/auth/models.py

homeassistant/auth/providers/__init__.py

homeassistant/auth/providers/homeassistant.py

homeassistant/auth/providers/insecure_example.py

homeassistant/auth/providers/legacy_api_password.py

homeassistant/auth/util.py

homeassistant/auth_providers/__init__.py

homeassistant/components/rachio.py

homeassistant/config.py

homeassistant/scripts/auth.py

tests/auth/__init__.py

tests/auth/providers/__init__.py

tests/auth/providers/test_homeassistant.py

tests/auth/providers/test_insecure_example.py

tests/auth/providers/test_legacy_api_password.py

tests/auth/test_init.py

tests/common.py