Add alias package kubernetes.client.apis with deprecation warning

Author: roycaihw

kubernetes/client/apis/__init__.py

@@ -0,0 +1,11 @@
+from __future__ import absolute_import
+import warnings
+
+# flake8: noqa
+
+# alias kubernetes.client.api package and print deprecation warning
+from kubernetes.client.api import *
+warnings.warn(
+    "The package kubernetes.client.apis is renamed and deprecated, use kubernetes.client.api instead (please note that the trailing s was removed).",
+    DeprecationWarning
+)