Improve test

Author: pgleeson

.travis.yml

@@ -21,6 +21,7 @@ script:
     - if [ ${TRAVIS_PYTHON_VERSION:O:1} == "3" ]; then exit 0 ; fi
 
     - pip install git+https://github.com/OpenSourceBrain/osb-model-validation
-    - 
+    - omv install PyNN
+    
     - omv all -V
     - omv list-engines