Use only pip-installed versions of python packages.

Author: adam-azarchs

.travis.yml

@@ -11,10 +11,7 @@ addons:
   apt:
     packages:
       - build-essential
-      - cython
-      - python-numpy
-      - python-pytest
-      - python-sklearn
+      - liblapack3
 
 install:
   - pip install numpy cython pytest scikit-learn