[testlib] introduce a RepoAccess class to easily create connection and request Each RepoAccess hold a session for a user and three helper function to help create Connection, ClientConnection of WebRequest related to this session. related to #2920299

# -*- coding: utf-8 -*-
# copyright %(year)s %(author)s, all rights reserved.
# contact %(author-web-site)s -- mailto:%(author-email)s
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%(long-license)s
"""%(distname)s specific hooks and operations"""