Rename install_openstacksdk to install_ansible_opensatcksdk to make it
clear this is part of the install-ansible role, and it's the
openstacksdk version used with ansible (might be important if we
switch to virtualenvs). This also clears up inconsistency when we add
ARA install options too.
Change-Id: Ie8cb3d5651322b3f6d2de9d6d80964b0d2822dce