Revert "Changing to test setup to use protocol V1 instead of protocol downgrade logic"

This reverts commit a1574e0297.

Following fix for negotiation in nosetest context for Python 3
PYTHON-409

tests/integration/__init__.py

@@ -59,7 +59,7 @@ def get_server_versions():
     if cass_version is not None:
         return (cass_version, cql_version)
 
-    c = Cluster(protocol_version=1)
+    c = Cluster()
     s = c.connect()
     row = s.execute('SELECT cql_version, release_version FROM system.local')[0]