Move wrapper prop to 2.1

Change-Id: Ib050a7c147867ae3d54f36f625808d7f3d3bc41b
(cherry picked from commit 09fbd3949bf1a6e0bf8861c3d5b75d0470c4025e)
diff --git a/wrapper/gradle-wrapper.properties b/wrapper/gradle-wrapper.properties
index 99dcde4..4f017a2 100644
--- a/wrapper/gradle-wrapper.properties
+++ b/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=../../external/gradle/gradle-2.0-bin.zip
+distributionUrl=../../external/gradle/gradle-2.1-bin.zip