Update README.md

Author: fpistm

Diff for: README.md

@@ -1,5 +1,5 @@
 # Arduino_Tools
 [![GitHub release](https://img.shields.io/github/release/stm32duino/Arduino_Tools.svg)](https://github.com/stm32duino/Arduino_Tools/releases/latest)
-[![GitHub commits](https://img.shields.io/github/commits-since/stm32duino/Arduino_Tools/2017.8.31.svg)](https://github.com/stm32duino/Arduino_Tools/compare/2017.8.31...master)
+[![GitHub commits](https://img.shields.io/github/commits-since/stm32duino/Arduino_Tools/2017.9.22.svg)](https://github.com/stm32duino/Arduino_Tools/compare/2017.9.22...master)
 
 Contains upload tools for STM32 based boards and some other usefull scripts (ex: [genpinmap](https://github.com/stm32duino/Arduino_Tools/tree/master/src/genpinmap))