title: Proguard error: there were 211 duplicate class definitions
body: <p>I am having the following error while exporting after integrating Scoreloop. Before that it was fine.</p>
  
  <pre><code>Proguard returned with error code 1. See console
  Note: there were 211 duplicate class definitions.
  You should check if you need to specify additional program jars.
  Exception in thread "main" java.lang.StackOverflowError
  at proguard.obfuscate.ClassObfuscator.visitEnclosingMethodAttribute(ClassObfuscator.java:182)
  .........
  .............
  </code></pre>
  
  <p>and probably more 210 number of errors which I didn't give here. I mentioned Scoreloop in proguard-project.txt the following way:</p>
  
  <pre><code>#############
  # Scoreloop #
  #############
  -dontwarn com.scoreloop.client.android.core.paymentprovider.**
  -keep class com.scoreloop.client.android.core.paymentprovider.fortumo.FortumoPaymentProviderController {*;}
  -keep class com.scoreloop.client.android.core.paymentprovider.fortumo.FortumoPaymentProvider {*;}
  -keep class com.scoreloop.client.android.core.paymentprovider.paypalx.PayPalXPaymentProviderController {*;}
  -dontwarn com.scoreloop.client.android.core.ui.WebViewDialog
  -keep class com.scoreloop.client.android.core.ui.WebViewDialog {*;}
  -keep class com.facebook.android.** {*;}
  </code></pre>
  
  <p>How to resolve these errors?</p>