add openturns in travis config

Author: relf

.travis.yml

@@ -10,9 +10,9 @@ jobs:
 
 install: 
   - pip install numpy cython 
-  - pip install smt salib
+  - pip install smt salib openturns
   - pip install -e .
   - pip list
 
 script:
-  - pytest
+  - pytest