Merge pull request #3764 from degasus/android

Android: Update gradle version

Source/Android/build.gradle

@@ -5,7 +5,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.0.0-beta5'
+        classpath 'com.android.tools.build:gradle:2.1.0-alpha5'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files