Update version to 2.1.1

Merge pull request #198 from graphql-python/prepare-2_1_1

Author: jnak

graphene_sqlalchemy/__init__.py

@@ -2,7 +2,7 @@
 from .fields import SQLAlchemyConnectionField
 from .utils import get_query, get_session
 
-__version__ = "2.1.0"
+__version__ = "2.1.1"
 
 __all__ = [
     "__version__",