Add test code coverage tracking

Author: jimhester

.Rbuildignore

@@ -13,3 +13,4 @@ doxyfile
 .clang_format
 vignettes/getCurrentVersionsOfCitedPackages.R
 ^Contributing.md$
+^\.codecov\.yml$

.codecov.yml

@@ -0,0 +1 @@
+comment: false

.travis.yml

@@ -22,6 +22,9 @@ install:
 script: 
   - ./run.sh run_tests
 
+after_success:
+  - R -e 'install.packages("covr")' -e 'covr::codecov()'
+
 after_failure:
   - ./run.sh dump_logs
 

README.md

@@ -1,4 +1,4 @@
-## Rcpp [![Build Status](https://travis-ci.org/RcppCore/Rcpp.svg)](https://travis-ci.org/RcppCore/Rcpp) [![License](http://img.shields.io/badge/license-GPL%20%28%3E=%202%29-brightgreen.svg?style=flat)](http://www.gnu.org/licenses/gpl-2.0.html) [![CRAN](http://www.r-pkg.org/badges/version/Rcpp)](https://cran.r-project.org/package=Rcpp) [![Downloads](http://cranlogs.r-pkg.org/badges/Rcpp?color=brightgreen)](http://www.r-pkg.org/pkg/Rcpp)
+## Rcpp [![Build Status](https://travis-ci.org/RcppCore/Rcpp.svg)](https://travis-ci.org/RcppCore/Rcpp) [![License](http://img.shields.io/badge/license-GPL%20%28%3E=%202%29-brightgreen.svg?style=flat)](http://www.gnu.org/licenses/gpl-2.0.html) [![CRAN](http://www.r-pkg.org/badges/version/Rcpp)](https://cran.r-project.org/package=Rcpp) [![Downloads](http://cranlogs.r-pkg.org/badges/Rcpp?color=brightgreen)](http://www.r-pkg.org/pkg/Rcpp) [![Coverage Status](https://img.shields.io/codecov/c/github/RcppCore/Rcpp/master.svg)](https://codecov.io/github/RcppCore/Rcpp?branch=master)
 
 ### Seamless R and C++ Integration