update GK

Author: ignatov

CONTRIBUTING.md

@@ -81,7 +81,7 @@ in the way we spend time to understand the problems and thus solve them.
 1. Checkout plugin repo and open the project
 1. Import the project from gradle
 1. Git revert changes to the .idea folder because IDEA Gradle import blows it away (https://youtrack.jetbrains.com/issue/IDEA-146295)
-1. Setup the right version of [Grammar-Kit](https://dl.dropboxusercontent.com/u/4294872/GrammarKit-21-08-2015.zip)
+1. Setup the right version of [Grammar-Kit](https://dl.dropboxusercontent.com/u/4294872/GrammarKit-2015-11-22.zip)
 1. Setup **Ant Support**, **UI Designer**, and **Gradle** plugins
 1. Run the **Go** run configuration