[travis] Add coveralls coverage history and stats

.travis.yml

 language: python
+branches:
+  only:
+    - master
+    - testing
 python:
 #  - "pypy"
 #  - "pypy3"
@@ -15,7 +19,13 @@ before_install:
   - if [[ $TRAVIS_PYTHON_VERSION != *"with_system_site_packages" ]]; then sudo apt-get install -qq gfortran; fi
   - if [[ $TRAVIS_PYTHON_VERSION == "2.7_with_system_site_packages" ]]; then sudo apt-get install -qq python-numpy python-scipy; fi
   - if [[ $TRAVIS_PYTHON_VERSION == "3.2_with_system_site_packages" ]]; then sudo apt-get install -qq python3-numpy python3-scipy; fi
+  - echo -e "[report]\nomit =\n    */python?.?/*\n    */site-packages/nose/*" > .coveragerc
+  - pip install coveralls
 install:
-  - pip install "file://$PWD#egg=pymdptoolbox[LP]"
+  - if [[ $TRAVIS_PYTHON_VERSION != *"with_system_site_packages" ]]; then pip install --upgrade "file://$PWD#egg=pymdptoolbox[LP]"; fi
+  - if [[ $TRAVIS_PYTHON_VERSION == *"with_system_site_packages" ]]; then pip install "file://$PWD#egg=pymdptoolbox[LP]"; fi
 # command to run tests
-script: nosetests
+script:
+  nosetests --with-coverage --cover-package=mdptoolbox
+after_success:
+  coveralls

README.rst

@@ -3,6 +3,8 @@ Markov Decision Process (MDP) Toolbox 4.0 for Python
 
 .. image:: https://travis-ci.org/sawcordwell/pymdptoolbox.svg?branch=master
     :target: https://travis-ci.org/sawcordwell/pymdptoolbox
+.. image:: https://coveralls.io/repos/sawcordwell/pymdptoolbox/badge.png
+  :target: https://coveralls.io/r/sawcordwell/pymdptoolbox
 
 The MDP toolbox provides classes and functions for the resolution of
 descrete-time Markov Decision Processes. The list of algorithms that have been