message: Unpack collections by default in the merger
  +change of logic to allow the user to shoot himself in the foot when
  directly merging collections - this is SLOOW and leaks due to ROOT's
  (lack of) ownership model.
diff: @@ -91,7 +91,7 @@ Bool_t fAllowResetOnRequest=kTRUE;
  Bool_t fAllowResetAtSOR=kTRUE;
  Bool_t fAllowClearAtSOR=kFALSE;
  -Bool_t fUnpackCollections = kFALSE;
  +Bool_t fUnpackCollections = kTRUE;
  Bool_t fUnpackContainers = kFALSE;
  Bool_t fFullyDestroyAnalysisDataContainer = kFALSE;
  std::string fLoadLibs;
  @@ -281,7 +281,7 @@ public:
  {
  mergeable = dynamic_cast<AliMergeable*>(fObject);
  }
  - else if (!fMergeCall && fObject->IsA())
  + if (!hist && !mergeable && !fMergeCall && fObject->IsA())
  {
  //use ROOT magic as last resort
  fMergeCall = new TMethodCall;
  