Reimplemented client shell
Reimplemented client shell

The shell now skips discovery of keystone versions or session creation
because all those details are encapsulated inside SDK.

We don't support server side authentication at the moment.

Argument parsing is moved out to a separate module.

openstack/python-senlinclient,stackforge/python-senlinclient,openstack/python-senlinclient,tengqm/python-senlinclient,stackforge/python-senlinclient,tengqm/python-senlinclient