Make $/.config/matplotlib to try to fix py35 errors.

Author: mcflugen

.travis.yml

@@ -51,6 +51,7 @@ install:
 - conda install --file=requirements.txt
 - conda info -a && conda list
 script:
+- mkdir -p $HOME/.config/matplotlib # For Python 3.5
 - travis_wait 50 pytest -vvv # the cellular atomata test takes over 10 minutes, and the entire process takes about 30 minutes, so we'll give it 50 min
 virtualenv:
   system_site_packages: false