Add keystone get-token.py utility

+ Can be used to validate that you switched from uuid to fernet
  tokens on a cloud

Example usages:

(Get a token from the undercloud)
[stack@ospd utils]$ . ../../stackrc
[stack@ospd utils]$ ./get-token.py
b8b597133d3040b1ad87381591f9965c

(Get a token from the overcloud)
[stack@ospd utils]$ . ../../overcloudrc
[stack@ospd utils]$ ./get-token.py
5968d8c4149f443d8f3484e0b8353bfa

(Get a token from overcloud after adjusting to fernet tokens)
[stack@ospd utils]$ ./get-token.py
gAAAAABXhlqfbX0n0MtiBXDLk2WSk7XLc1cKzQ4Q6Xmb8MjGHgEFGYRu ...

Change-Id: Idfba4848b35e05023ea2a32bd830c5d0d50e685a

utils/get-token.py

@@ -0,0 +1,32 @@
+#!/usr/bin/env python
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+"""Gets a token using rc file credentials."""
+from keystoneclient.v2_0 import client
+import os
+import sys
+
+os_auth_url = os.environ.get('OS_AUTH_URL')
+os_username = os.environ.get('OS_USERNAME')
+os_password = os.environ.get('OS_PASSWORD')
+
+if os_auth_url is None or os_username is None or os_password is None:
+    print "source rc file(stackrc/overcloudrc etc) before running."
+    sys.exit(1)
+
+project_scoped = client.Client(
+    username=os_username,
+    password=os_password,
+    project_name='admin',
+    auth_url=os_auth_url)
+
+print('%s' % project_scoped.auth_token)