Allow managing cloud webhook (#18672)

* Add cloud webhook support

* Simplify payload

* Add cloud http api tests

* Fix tests

* Lint

* Handle cloud webhooks

* Fix things

* Fix name

* Rename it to cloudhook

* Final rename

* Final final rename?

* Fix docstring

* More tests

* Lint

* Add types

* Fix things

homeassistant/components/cloud/const.py

@@ -6,6 +6,7 @@ REQUEST_TIMEOUT = 10
 PREF_ENABLE_ALEXA = 'alexa_enabled'
 PREF_ENABLE_GOOGLE = 'google_enabled'
 PREF_GOOGLE_ALLOW_UNLOCK = 'google_allow_unlock'
+PREF_CLOUDHOOKS = 'cloudhooks'
 
 SERVERS = {
     'production': {
@@ -16,7 +17,8 @@ SERVERS = {
         'google_actions_sync_url': ('https://24ab3v80xd.execute-api.us-east-1.'
                                     'amazonaws.com/prod/smart_home_sync'),
         'subscription_info_url': ('https://stripe-api.nabucasa.com/payments/'
-                                  'subscription_info')
+                                  'subscription_info'),
+        'cloudhook_create_url': 'https://webhook-api.nabucasa.com/generate'
     }
 }