Don't install scripts straight to /usr/local/bin

This results in more then just the openstack clients getting installed
to /usr/local/bin. In my case /usr/local/bin/pip was part of the
python-novaclient virtualenv and being used globally. Instead link to
what we want inside the virtualenv.

Change-Id: If44b397cdd80c46bf5a2a86d7369a4d74e09b58c
Merge "Don't install scripts straight to /usr/local/bin"