CSV Column reordering, editing, addition, removal

Support for CSV column manipulations, including column reordering, hiding, removal, addition, and renaming. Column based operations, other than temporary hiding, are considered document changing, and while registered with the Undo manager, are destructive to the original document when saved. For datasets smaller than the Cache limit this is should be an in memory change to the document representation. For datasets larger than the Cache limit these changes should be recorded in the editing metadata for later application.