I did:
python -m pip install --upgrade pip

and then
pip3 install cmake
went OK.

So I would suggest to change notices like "You are using pip version 7.1.2, however version 9.0.1 is available.
You should consider upgrading via the 'python -m pip install --upgrade pip' comm
and." into errors or warning so they seem more like something user has to do rather than something he might consider doing.