Added normalization of IPv6 addresses

* Added IPy IPv6 normalization to server and address models

Change-Id: I1ee8156c9a392620604e9f8738b6e43a124c2091
pep8 compliance
added version model
added check for link dict having key type
added _list_to_obj for MediaTypes
added to obj methods for version class
added tags to classes, fixed a inhertiance class reference for Role class
Cleanup of servers client

* Fixed pep8 issues with servers client
* Added epydoc descriptions to methods

Change-Id: I772b6a8ac897688496ce57146297c87d4cdcb9cc
Merge "Added normalization of IPv6 addresses"
added extensions api, and base class
moved version to its own api
fixed endline
added init file for respones model
added user class for users_api
added tenant class to tenant api
fixed spelling error
replaced root_tag with tag
fixed method declaration
added roles class for tenants_api
initial push of tenants_api client