Remove ParCompactionManager::Action enum

From psCompactionManager.hpp:
// ------------------------ Don't putback if not needed
  // Actions that the compaction manager should take.
  enum Action {
    Update,
    Copy,
    UpdateAndCopy,
    CopyAndUpdate,
    NotValid
  };
// ------------------------ End don't putback if not needed

This code is from the initial push and from what I can see it is not need but was "putback" anyway. It might have been needed, but we should see if we can remove it now. From what I saw when doing a quick scan an action is set in the constructor, but then never considered during the collection.