PYTHON-1782 Restore backwards compatibility of MongoClient initialization when passing a type_registry

(cherry picked from commit 76ef2b4)

Author: prashantmital

pymongo/mongo_client.py

@@ -95,9 +95,9 @@ def __init__(
  host=None,
  port=None,
  document_class=dict,
- type_registry=None,
  tz_aware=None,
  connect=None,
+ type_registry=None,
  **kwargs):
  """Client for a MongoDB instance, a replica set, or a set of mongoses.