Patch to add insert of multiple tuples per INSERT statement

The attached patch adds the ability to explicitly insert multiple tuples
per insert statement. ie:

INSERT INTO tab [(col1, col2, ...)] VALUES (x1, y1, ...), (x2, y2, ...), ... ;

as per the todo list entry.

Liam

--
Liam Stewart :: Red Hat Canada, Ltd. :: liams(at)redhat(dot)com