class AliMUONVStore: public TObject

 \class AliMUONVStore

 A store is a container, which can be searched for (using FindObject methods),
 iterated upon (using CreateIterator() method), and into which you can
 add objects (using Add)

 In addition, a store can be connected to a TTree.

 The general way of dealing with I/O for MUON is a two stage process :

 1) first get a TTree pointer using the AliLoader mechanism (this is AliRoot
    general)

 2) connect that TTree to a MUON (virtual) data container using
    the container's Connect(TTree&) method (this is MUON specific)

 Example for reading digits for nevents

 \code

 AliMUONVDigitStore* digitStore(0x0);

 AliLoader* loader = ... ( get loader from somewhere, e.g. AliRunLoader::GetDetectorLoader());
 loader->LoadDigits("READ"); // load digits

 for ( Int_t i = 0; i < nevents; ++i )
 {
   TTree* treeD = loader->TreeD(); // get the tree
   if (!digitStore) digitStore = static_cast<AliMUONVDigitStore*>
     (AliMUONVDigitStore::CreateStore(*treeD,"Digit")); // creates a container for digits
   (concrete class is given by the tree itself)
   digitStore->Connect(*treeD);
   treeD->GetEvent(0); // actual reading of the data

   the digitStore is now filled and ready to be used
   ....

   digitStore->Clear(); // reset once used
 }

 \endcode

 Please note that for reading data, you do *not* need to know the concrete
 container class, as it is given to you by the TTree

 Example for writing digits

 \code

 get the loader and do a loader->LoadDigits("RECREATE" or "UPDATE")
 (generally done by the framework itself)

 AliMUONVDigitStore* digitStore = new AliMUONDigitStoreV1
 // for writing, must decide on the concrete store class to use

 for ( Int_t i = 0; i < nevents; ++i )
 {
   TTree* treeD = loader->TreeD();
   digitStore->Connect(*treeD);

   ... put some digits in the digitStore

   treeD->Fill();

   loader->WriteDigits("OVERWRITE");
 }

 delete digitStore;

 loader->UnloadDigits();

 \endcode

 In the write case, one *must* specify a concrete class for the container