Add coveralls badge to README (tracks coverage for master only)
@@ -10,7 +10,7 @@ STYLE CONVENTION USED
**`function`**
**`type`** or **`structure`**
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-# CCL [![Build Status](https://travis-ci.org/LSSTDESC/CCL.svg?branch=master)](https://travis-ci.org/LSSTDESC/CCL)
+# CCL [![Build Status](https://travis-ci.org/LSSTDESC/CCL.svg?branch=master)](https://travis-ci.org/LSSTDESC/CCL) [![Coverage Status](https://coveralls.io/repos/github/LSSTDESC/CCL/badge.svg?branch=master)](https://coveralls.io/github/LSSTDESC/CCL?branch=master)
LSST DESC Core Cosmology Library (`CCL`) provides routines to compute basic cosmological observables with validated numerical accuracy.
The library is written in C99 and all functionality is directly callable from C and C++ code. We also provide python bindings for higher-level functions.
