Issue #6: type attributes
Issue #6: type attributes

changed unitDate, dsc, and list element @type to unitdateType, dscType,
and listType per issue #6

SAA-SDT/EAD3,SAA-SDT/EAD-Revision,informaticmonad/EAD3,informaticmonad/EAD3,SAA-SDT/EAD-Revision,SAA-SDT/EAD3