Move to setting maven version via SupporLibrary extension.

Test: ./gradlew createArchive
Change-Id: Ifa145712bc3b68ef561d8d7f9e21e97c79b705d1
diff --git a/fragment/build.gradle b/fragment/build.gradle
index 95886be..dfb6ca9 100644
--- a/fragment/build.gradle
+++ b/fragment/build.gradle
@@ -1,4 +1,5 @@
 import android.support.LibraryGroups
+import android.support.LibraryVersions
 
 plugins {
     id("SupportAndroidLibraryPlugin")
@@ -25,6 +26,7 @@
 supportLibrary {
     name = "Android Support Library fragment"
     publish = true
+    mavenVersion = LibraryVersions.SUPPORT_LIBRARY
     mavenGroup = LibraryGroups.SUPPORT
     inceptionYear = "2011"
     description = "The Support Library is a static library that you can add to your Android application in order to use APIs that are either not available for older platform versions or utility APIs that aren\'t a part of the framework APIs. Compatible on devices running API 14 or later."