Fix address validation rule to allow 'all' keyword

The rule was looking for the keyword 'any' but should have been looking for 'all' 

http://nginx.org/en/docs/http/ngx_http_access_module.html

backend/schema/endpoints/access-lists.json

@@ -35,7 +35,7 @@
 				},
 				{
 					"type": "string",
-					"pattern": "^any$"
+					"pattern": "^all$"
 				}
 			]
 		},