Update Support library gradle build files WIP

Means we can now develop the support lib using
Android Studio and Gradle.

Need to update the Gradle prebuilts.

Change-Id: I788c6105185b5681267d6ad9a8a8b875fc4e57a6
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index 127125b..800b59f 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=../../../../tools/external/gradle/gradle-1.11-bin.zip
+distributionUrl=../../../../tools/external/gradle/gradle-2.2.1-bin.zip