Cleanup setup and requirements

[itziakos]

This PR tries to fix the requirements for kiva and enable and at the same time clean-up the travis-ci build

[itziakos]

Please note that now the PR tests take only 7 minutes instead of 12-14.

[jwiggins]

Not used here

[jwiggins]

Other than that unused import I'm 👍 on this PR

[jwiggins]

Go ahead and merge as soon as Travis gives the OK. I'm going offline for a bit.

[itziakos]

Ok we now pass the setup.py import and we arrive at a new issue which now is the result of the interaction between setuptools and numpy.distutils. It looks that if any packages are in the install_requires list, we get an out of memory error when one of the required packages is installed.

So, that is why commit 14e11492 fails, because it will cause the required packages to be downloaded by the combined setuptools/numpy.distutils setup.py. I have been able to replicate the behaviour locally.

[itziakos]

So it looks that the last version of setuptools that work is 9.1