Update readme.md

Author: dsarrut

readme.md

@@ -4,7 +4,7 @@ https://github.com/OpenGATE/Gate is the public repository of the GATE software.
 
 More details on: http://www.opengatecollaboration.org
 
-* The stable version is branch 'master' (or tag 8.1): https://github.com/OpenGATE/Gate/tree/v8.1
+* The stable version is branch 'master' (or tag 8.2): https://github.com/OpenGATE/Gate/tree/v8.2
 * The current development version is branch 'develop' (default): http://github.com/OpenGATE/Gate/tree/develop
 * Dashboard of daily compilation: http://my.cdash.org/index.php?project=GATE
 * Examples: https://github.com/OpenGATE/GateContrib