add coveralls to build process

.travis.yml

@@ -3,6 +3,12 @@ python:
   - "2.7"
   
 # command to install dependencies, e.g. pip install -r requirements.txt --use-mirrors
-install: pip install -r requirements.txt
+install: 
+     - "pip install -r requirements.txt"
+     - "pip install coveralls"
 # command to run tests, e.g. python setup.py test
-script:  python setup.py test
+script:  
+    coverage run --source=pwman setup.py test
+
+after_success:
+      coveralls