Update README.md

Author: simonsays1980

README.md

@@ -1,4 +1,7 @@
-[![R-CMD-check](https://github.com/simonsays1980/bayespin/actions/workflows/r-cmd-check.yml/badge.svg?branch=documentation)](https://github.com/simonsays1980/bayespin/actions/workflows/r-cmd-check.yml)
+[![R-CMD-check](https://github.com/simonsays1980/bayespin/actions/workflows/r-cmd-check.yml/badge.svg?branch=documentation)](https://github.com/simonsays1980/bayespin/actions/workflows/r-cmd-check.yml) [![GPLv3 license](https://img.shields.io/badge/License-GPLv3-blue.svg)](http://perso.crans.org/besson/LICENSE.html) 
+[![Linux](https://svgshare.com/i/Zhy.svg)](https://svgshare.com/i/Zhy.svg) [![macOS](https://svgshare.com/i/ZjP.svg)](https://svgshare.com/i/ZjP.svg) [![Windows](https://svgshare.com/i/ZhY.svg)](https://svgshare.com/i/ZhY.svg)
+
+
 
 # bayespin
 **An R package for Bayesian estimation of the probability of informed trading**
@@ -126,4 +129,4 @@ Journal of Finance 46, 733-746.
 
 ## Some more information
 This is a package worked on for years and still not fully implemented. As it is
-still maintained by a single author, please by patient with issues.
+still maintained by a single author, please by patient with issues.