NameValueTable usage is confusing due to its getValue() method, and subclasses'
getValue(int rowIndex) methods.  We probably don't need/want these methods at
all, since t:dataTable JSF cmpnts should simply be obtaining rendered cell
values from the current row object.

Also, we should probably just replace this impl with e.h.m.s.u.table.DataTable.
Perhaps in a way thay allows all of the sophisticated search/nav/col filtering
functionality to be hidden. If we do this, we should add appropriate new
TableColumn classes to replicate any special case cell types that are not
already supported (e.g. link list values, image values).