Merge pull request #40 from edx/clee/remove_double_travis

Update .travis.yml

.travis.yml

@@ -7,5 +7,8 @@ install:
   - "pip install coveralls"
 script:
   - "python manage.py test"
+branches:
+    only:
+      - master
 after_success:
-  coveralls
\ No newline at end of file
+  coveralls