Update README.md

Author: abbysko

README.md

@@ -3,6 +3,7 @@ Version 1.0
 
 
 [![View Horizon Chart on File Exchange](https://www.mathworks.com/matlabcentral/images/matlab-file-exchange.svg)](https://www.mathworks.com/matlabcentral/fileexchange/133607-horizon-chart)
+[![Open in MATLAB Online](https://www.mathworks.com/images/responsive/global/open-in-matlab-online.svg)](https://matlab.mathworks.com/open/github/v1?host=www.mathworks.com&repo=matlabcentral/fileexchange)
 
 ![](horizonFig.png)
 
@@ -46,4 +47,4 @@ n_stocks = 5;
 basicHorizonChart = horizonChart(x_data, y_data, 5);
 
 
-```
+```