Add test coverage with coveralls.io

.travis.yml

@@ -30,9 +30,12 @@ install:
   - conda create -q -n testenv python=${PYTHON} root=${ROOT} rootpy pandas nose
   - export CONDA_ENV_PATH=$HOME/miniconda/envs/testenv
   - source activate testenv
+  - pip install coverage coveralls
 
 script: nosetests
-#after_success:
-#    - time coveralls
+
+after_success:
+    - time coveralls
+
 notifications:
     email: false

README.md

@@ -1,7 +1,10 @@
 
 # root\_pandas
 
-[![Build Status](https://travis-ci.org/scikit-hep/root_pandas.svg?branch=master)](https://travis-ci.org/scikit-hep/root_pandas) [![PyPI](https://badge.fury.io/py/root_pandas.svg)](https://pypi.python.org/pypi/root_pandas/) [![DOI](https://zenodo.org/badge/17171/ibab/root_pandas.svg)](https://zenodo.org/badge/latestdoi/17171/ibab/root_pandas)
+[![Build Status](https://travis-ci.org/scikit-hep/root_pandas.svg?branch=master)](https://travis-ci.org/scikit-hep/root_pandas)
+[![Coverage Status](https://coveralls.io/repos/github/scikit-hep/root_pandas/badge.svg?branch=master)](https://coveralls.io/github/scikit-hep/root_pandas?branch=master)
+[![PyPI](https://badge.fury.io/py/root_pandas.svg)](https://pypi.python.org/pypi/root_pandas/)
+[![DOI](https://zenodo.org/badge/17171/ibab/root_pandas.svg)](https://zenodo.org/badge/latestdoi/17171/ibab/root_pandas)
 
 `root_pandas` is a convenience package built around the `root_numpy` library.
 It allows you to easily load and store pandas DataFrames using the columnar ROOT data format used in high energy physics.