add missing types to Session and Query (#233)

Author: slaroche

sqlalchemy-stubs/orm/query.pyi

@@ -45,7 +45,7 @@ class Query(Generic[_T]):
     def with_entities(self, *entities): ...
     def add_columns(self, *column): ...
     def add_column(self, column): ...
-    def options(self, *args): ...
+    def options(self: _Q, *args) -> _Q: ...
     def with_transformation(self, fn): ...
     def with_hint(self, selectable, text, dialect_name: str = ...): ...
     def with_statement_hint(self, text, dialect_name: str = ...): ...

sqlalchemy-stubs/orm/session.pyi

@@ -61,7 +61,7 @@ class Session(_SessionClassMethods):
                mapper: Optional[Any] = ..., bind: Optional[Any] = ..., **kw): ...
     def close(self) -> None: ...
     def invalidate(self) -> None: ...
-    def expunge_all(self): ...
+    def expunge_all(self) -> None: ...
     def bind_mapper(self, mapper, bind): ...
     def bind_table(self, table, bind): ...
     def get_bind(self, mapper: Optional[Any] = ..., clause: Optional[Any] = ...): ...
@@ -77,7 +77,7 @@ class Session(_SessionClassMethods):
     def expire_all(self) -> None: ...
     def expire(self, instance, attribute_names: Optional[Any] = ...) -> None: ...
     def prune(self): ...
-    def expunge(self, instance): ...
+    def expunge(self, instance) -> None: ...
     def add(self, instance, _warn: bool = ...) -> None: ...
     def add_all(self, instances) -> None: ...
     def delete(self, instance): ...