Changed the metadata json files in the download to have more specific names and not to adjust if a file exists with that name.  Removed explicit sorting in zip file creation and adjusted the testsing to permit this.
I refactored how deleting resources was done to avoid the double loop through the models and individual ids.  It was deemed better to have a partial deletion than the inefficiency.  Also, I extended all of the models so that the remove method can get passed a progress context and so that the subtreeCount returns something for that model.  This allows better progress of resource deletion.