Travis: Add Py3.6, use py.test, use binary numpy/scipy

.requirements-full-test.txt

+numpy
+scipy
+simpletraj
+mdtraj
+mdanalysis
+pytest

.travis.yml

@@ -4,8 +4,12 @@ python:
   - "3.3"
   - "3.4"
   - "3.5"
+  - "3.6"
 cache:
     directories:
         - $HOME/.cache/pip
-install: "pip install -r requirements.txt"
-script: nosetests -v
+install:
+    - pip --upgrade pip setuptools wheel
+    - pip install -r .requirements-full-test.txt --only-binary=numpy,scipy
+script:
+    - py.test test/