Move ansible to virtualenv in kolla_toolbox
Move ansible to virtualenv in kolla_toolbox

Now the ansible and its python dependencies are installed on system. It
may be failed to install in some case. This patch installs python
packages in virtualenv for kolla_toolbox image.

Closes-Bug: #1771717
Change-Id: I3c4465d5dfe4f909521fa00173f1cf8d9eec783f

stackforge/kolla,rahulunair/kolla,openstack/kolla,openstack/kolla,stackforge/kolla,rahulunair/kolla,stackforge/kolla