Fix boto syntax

Boto library is changed, so an example need to be updated.
- Change boto.s3.Connection to boto.s3.connection.S3Connection, it's the
  right syntax.
- Remove calling_format arg, is unnecessary and in some cases, it doesn't
  works. Default calling_format(DefaultCallingFormat) worked fine.
- Update an example client using boto3 library.
- Note libraries version.

Change-Id: If02edd337e451aff257fa9db920f2bfbf230d924
Closes-Bug: #1660387

doc/config-reference/source/object-storage/configure-s3.rst

@@ -78,15 +78,38 @@ To set up your client, ensure you are using the ec2 credentials, which
 can be downloaded from the API Endpoints tab of the dashboard. The host
 should also point to the Object Storage node's hostname. It also will
 have to use the old-style calling format, and not the hostname-based
-container format. Here is an example client setup using the Python boto
-library on a locally installed all-in-one Object Storage installation.
+container format. Here are two examples of client setup using both Python
+boto_ library (version 2.45.0) and boto3_(version 1.4.4) library on a locally
+installed all-in-one Object Storage installation.
 
 .. code-block:: python
 
-    connection = boto.s3.Connection(
+    # Connection using boto library
+    connection = boto.s3.connection.S3Connection(
         aws_access_key_id='a7811544507ebaf6c9a7a8804f47ea1c',
         aws_secret_access_key='a7d8e981-e296-d2ba-cb3b-db7dd23159bd',
         port=8080,
         host='127.0.0.1',
-        is_secure=False,
-        calling_format=boto.s3.connection.OrdinaryCallingFormat())
+        is_secure=False)
+
+    # Connection using boto3 library
+
+    # Create a low-level service client
+    s3_client = boto3.client(
+        's3',
+        aws_access_key_id='a7811544507ebaf6c9a7a8804f47ea1c',
+        aws_secret_access_key='a7d8e981-e296-d2ba-cb3b-db7dd23159bd',
+        endpoint_url='http://127.0.0.1:8080'
+    )
+
+    #  Create a resource service client
+    s3_resource = boto3.resource(
+        's3',
+        aws_access_key_id='a7811544507ebaf6c9a7a8804f47ea1c',
+        aws_secret_access_key='a7d8e981-e296-d2ba-cb3b-db7dd23159bd',
+        endpoint_url='http://127.0.0.1:8080'
+    )
+
+.. _boto: https://github.com/boto/boto
+
+.. _boto3: https://github.com/boto/boto3/