As get-pip.py evolves based on pip 10, while we're still using
pip 9, changes in the way it can be used are causing problems.
For example, the ability to use --download is no longer there.
As such, let's pin to a known good version and leave it at that
until we no longer need to use this script. Version 3.2 maps to
pip 7.1.2 which fulfills our needs.
Change-Id: I96228099c8087ffaad8673184aa0bdddfb44023d
15c12437a2