Change mock version

Author: LD250

.travis.yml

@@ -4,7 +4,7 @@ python:
     - "3.4"
     - "3.5"
 install:
-    - pip install flake8 mock==1.3.0
+    - pip install flake8 mock==2.0.0
 script:
     - flake8 
     - python setup.py test