Gradle: Upgrade the gradle-versions-plugin to the latest version

See https://github.com/ben-manes/gradle-versions-plugin/releases

Change-Id: Ifad3fa3b75671abb5d6256f2fb5deee243804261

build.gradle

diff --git a/build.gradle b/build.gradle
index 51411b1..d95bf48 100644
--- a/build.gradle
+++ b/build.gradle
@@ -13,7 +13,7 @@
 
     dependencies {
         classpath 'com.android.tools.build:gradle:2.2.0'
-        classpath 'com.github.ben-manes:gradle-versions-plugin:0.12.0'
+        classpath 'com.github.ben-manes:gradle-versions-plugin:0.13.0'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files