Add networks_nsxt dir, simple example

Define a directory for NSX-T sample code. Add a basic
example that shows how to authenticate to VMC/NSX-T and
make a simple read call.

Signed-Off-By: Gordon Good <ggood@vmware.com>

samples/vmc/networks_nsxt/hello_world.py

@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+
+"""
+* *******************************************************
+* Copyright (c) VMware, Inc. 2019. All Rights Reserved.
+* SPDX-License-Identifier: MIT
+* *******************************************************
+*
+* DISCLAIMER. THIS PROGRAM IS PROVIDED TO YOU "AS IS" WITHOUT
+* WARRANTIES OR CONDITIONS OF ANY KIND, WHETHER ORAL OR WRITTEN,
+* EXPRESS OR IMPLIED. THE AUTHOR SPECIFICALLY DISCLAIMS ANY IMPLIED
+* WARRANTIES OR CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY,
+* NON-INFRINGEMENT AND FITNESS FOR A PARTICULAR PURPOSE.
+"""
+
+__author__ = 'VMware, Inc.'
+
+import argparse
+import pprint
+
+from com.vmware.nsx_policy_client_for_vmc import (
+    create_nsx_policy_client_for_vmc)
+
+
+class AuthExample(object):
+    """
+    Demonstrates how to authenticate to VMC using the NSX-T SDK
+    and perform a simple read operation.
+
+    Sample Prerequisites:
+        - An organization associated with the calling user.
+        - A SDDC in the organization
+    """
+
+    def __init__(self):
+        parser = argparse.ArgumentParser(
+            formatter_class=argparse.ArgumentDefaultsHelpFormatter)
+        parser.add_argument('-r', '--refresh-token',
+                            required=True,
+                            help='VMware Cloud API refresh token')
+
+        parser.add_argument('-o', '--org-id',
+                            required=True,
+                            help='Organization identifier.')
+
+        parser.add_argument('-s', '--sddc-id',
+                            required=True,
+                            help='Sddc Identifier.')
+
+        args = parser.parse_args()
+
+        self.org_id = args.org_id
+        self.sddc_id = args.sddc_id
+        self.vmc_client = create_nsx_policy_client_for_vmc(
+            args.refresh_token, args.org_id, args.sddc_id)
+
+    def get_domains(self):
+        print('\n# Get Domains: List network domains:')
+        domains = self.vmc_client.infra.Domains.list()
+        pprint.pprint(domains)
+
+
+def main():
+    auth_example = AuthExample()
+    auth_example.get_domains()
+
+if __name__ == '__main__':
+    main()