move from signals to apps, add dedicated feature docs, add config toggle to menu item, undo unnecessary changes

cookbook/signals.py

@@ -4,12 +4,11 @@ from django.conf import settings
 from django.contrib.auth.models import User
 from django.contrib.postgres.search import SearchVector
 from django.core.cache import caches
-from django.db.models.signals import post_save, post_delete
+from django.db.models.signals import post_save
 from django.dispatch import receiver
 from django.utils import translation
 from django_scopes import scope, scopes_disabled
 
-from cookbook.connectors.connector_manager import ConnectorManager
 from cookbook.helper.cache_helper import CacheHelper
 from cookbook.helper.shopping_helper import RecipeShoppingEditor
 from cookbook.managers import DICTIONARY
@@ -162,9 +161,3 @@ def clear_unit_cache(sender, instance=None, created=False, **kwargs):
 def clear_property_type_cache(sender, instance=None, created=False, **kwargs):
     if instance:
         caches['default'].delete(CacheHelper(instance.space).PROPERTY_TYPE_CACHE_KEY)
-
-
-if not settings.DISABLE_EXTERNAL_CONNECTORS:
-    handler = ConnectorManager()
-    post_save.connect(handler, dispatch_uid="connector_manager")
-    post_delete.connect(handler, dispatch_uid="connector_manager")