Add coveralls to travis configuration

.travis.yml

@@ -7,5 +7,9 @@ python:
   - "3.3"
 install:
   - "pip install nose"
+  - "pip install python-coveralls"
   - "curl -s http://www.defunct.cc/maxmind-geoip-samples.tar.gz | tar -xzC tests/"
-script: nosetests
+script:
+  - nosetests
+after_success:
+  - coveralls