add coveralls badge to README, coveralls debugging

.travis.yml

@@ -7,7 +7,9 @@ install:
     - "pip install coveralls"
 env: SECRET_KEY=justfortravis
 script: "coverage run --source nsupdate --omit '*/migrations/*,*/_tests/*' -m py.test --pep8"
-after_success: coveralls
+after_success:
+    - coveralls debug
+    - coveralls
 notifications:
     email:
         recipients:

README.rst

@@ -13,6 +13,9 @@ https://github.com/nsupdate-info/nsupdate.info
 .. image:: https://travis-ci.org/nsupdate-info/nsupdate.info.png
     :target: https://travis-ci.org/nsupdate-info/nsupdate.info
 
+.. image:: https://coveralls.io/repos/nsupdate-info/nsupdate.info/badge.png
+        :target: https://coveralls.io/r/nsupdate-info/nsupdate.info
+
 .. image:: https://badge.fury.io/py/nsupdate.png
     :target: http://badge.fury.io/py/nsupdate