Add coveralls.io testing

Author: jdlangs

.travis.yml

@@ -17,6 +17,8 @@ before_script:
   - sleep 5
   - python test/echonode.py &
   - sleep 5
+after_success:
+  - julia -e 'cd(Pkg.dir("RobotOS")); Pkg.add("Coverage"); using Coverage; Coveralls.submit(Coveralls.process_folder())'
 after_script:
   - killall roscore
   - killall python

README.md

@@ -1,6 +1,7 @@
 # RobotOS.jl
 
 [![Build Status](https://travis-ci.org/phobon/RobotOS.jl.svg?branch=master)](https://travis-ci.org/phobon/RobotOS.jl)
+[![Coverage Status](https://coveralls.io/repos/phobon/RobotOS.jl/badge.svg?branch=master)](https://coveralls.io/r/phobon/RobotOS.jl?branch=master)
 
 ## Overview