Always install test reqs with -U flag

.travis.yml

@@ -7,9 +7,9 @@ cache:
   directories:
     - $HOME/.cache/pip
 install:
-  - pip install -r test-requirements.txt
+  - pip install -r test-requirements.txt -U
   - python setup.py develop
   - pip freeze
-script: py.test -r w --cov=./
+script: py.test --cov=./
 after_success:
   - codecov