Add Gradle 1.6

Change-Id: I728b9424d7d984e5aa9a36f6463a56f2a06cf2c2
diff --git a/PREBUILT b/PREBUILT
index 3f26046..0887da8 100644
--- a/PREBUILT
+++ b/PREBUILT
@@ -2,4 +2,5 @@
 
 http://services.gradle.org/distributions/gradle-1.3-all.zip
 http://services.gradle.org/distributions/gradle-1.4-all.zip
-http://services.gradle.org/distributions/gradle-1.5-all.zip
\ No newline at end of file
+http://services.gradle.org/distributions/gradle-1.5-all.zip
+http://services.gradle.org/distributions/gradle-1.6-all.zip
\ No newline at end of file