From Leandro:

Add new option to run with parallel unzipping in a separate thread.
To run it do
  Event 5000 1 99 1    (to write the file Event.root)
  Event 5000 1 99 20   (to read normal without a thread)
  Event 5000 1 99 21   (to read with the parallelp unzipping thread)
Send the results to rootdev@root.cern.ch


git-svn-id: http://root.cern.ch/svn/root/trunk@23762 27541ba8-7e3a-0410-8455-c3a389f83636