Add schema_extra and title in docs for Config sub-class

docs/index.rst

@@ -752,6 +752,7 @@ Behaviour of pydantic can be controlled via the ``Config`` class on a model.
 
 Options:
 
+:title: title for the generated JSON Schema
 :anystr_strip_whitespace: strip or not trailing and leading whitespace for str & byte types (default: ``False``)
 :min_anystr_length: min length for str & byte types (default: ``0``)
 :max_anystr_length: max length for str & byte types (default: ``2 ** 16``)
@@ -777,6 +778,7 @@ Options:
 :alias_generator: callable that takes field name and returns alias for it
 :keep_untouched: tuple of types (e. g. descriptors) that won't change during model creation and won't be
   included in the model schemas.
+:schema_extra: takes a ``dict`` to extend/update the generated JSON Schema
 
 .. warning::