Remove AutoVersionClient

Just do Client(version='auto').
Signed-off-by: Ben Firshman <ben@firshman.co.uk>

docker/__init__.py

@@ -3,4 +3,4 @@ from .version import version, version_info
 __version__ = version
 __title__ = 'docker-py'
 
-from .client import Client, AutoVersionClient, from_env  # flake8: noqa
+from .client import Client, from_env  # flake8: noqa

docker/client.py

@@ -400,13 +400,3 @@ class Client(
     @property
     def api_version(self):
         return self._version
-
-
-class AutoVersionClient(Client):
-    def __init__(self, *args, **kwargs):
-        if 'version' in kwargs and kwargs['version']:
-            raise errors.DockerException(
-                'Can not specify version for AutoVersionClient'
-            )
-        kwargs['version'] = 'auto'
-        super(AutoVersionClient, self).__init__(*args, **kwargs)

tests/integration/api_test.py

@@ -122,17 +122,6 @@ class AutoDetectVersionTest(unittest.TestCase):
         self.assertEqual(client_version, api_version_2)
         client.close()
 
-    def test_auto_client(self):
-        client = docker.AutoVersionClient(**kwargs_from_env())
-        client_version = client._version
-        api_version = client.version(api_version=False)['ApiVersion']
-        self.assertEqual(client_version, api_version)
-        api_version_2 = client.version()['ApiVersion']
-        self.assertEqual(client_version, api_version_2)
-        client.close()
-        with self.assertRaises(docker.errors.DockerException):
-            docker.AutoVersionClient(version='1.11', **kwargs_from_env())
-
 
 class ConnectionTimeoutTest(unittest.TestCase):
     def setUp(self):