HML Checker

When the view is activated make sure a new undo buffer is setup, and that undoing doesn't go back into the Table view undo buffer. Undos/Redos will only work for the current view session until left, and each undo/redo will also un-mark products as "Reviewed" and jump to the last un/re-edited product in this view.

When the view is exited make sure the undo buffer isn't left in place and appended to the existing undo buffer. Jump back into this view when undone by the Table view's undo buffer.