Marks on d.cursor?

[Tuomas Lukka <lukka@xxxxxxxxxxx>]

I was just thinking about d.mark and d.cursor: d.mark needs to have quite 
similar semantics to d.cursor, for example being able to mark past
versions of cells etc. is vital. So I was thinking that a mark could
actually just be a list of cursors, as then we wouldn't have to encode the
same special cases for two separate dimensions. The only problem is if you
want to put a cursor on a marking cell.

Ted, what do you think?

	Tuomas