Gradle version bump.

build.gradle

@@ -242,5 +242,5 @@ buildscript {
 }
 
 task wrapper(type: Wrapper) {
-    gradleVersion = '2.1'
+    gradleVersion = '2.2.1'
 }

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Mon Sep 15 11:05:29 BST 2014
+#Thu Nov 27 00:40:06 GMT 2014
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=http\://services.gradle.org/distributions/gradle-2.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-2.2.1-bin.zip