Fix for single/multi choice selection callback getting wrong index.

sample/build.gradle

@@ -8,7 +8,7 @@ android {
         applicationId "com.afollestad.materialdialogssample"
         minSdkVersion 14
         targetSdkVersion 21
-        versionCode 11
+        versionCode 12
         versionName "1.0"
     }
     buildTypes {