pgsql-server: Update DELETE FROM: < * Allow DELETE to handle table

Log Message:
-----------
Update DELETE FROM:

< * Allow DELETE to handle table aliases for self-joins
> * Allow an alias to be provided for the target table in UPDATE/DELETE
276,279c276,282
<   There is no way to create a table alias for the deleted table for use
<   in the DELETE WHERE clause.  The agreed approach is to allow a USING
<   clause to specify additional tables.  UPDATE already has an optional
<   FROM clause for this purpose.
>   This is not SQL-spec but many DBMSs allow it.
>
> * Allow additional tables to be specified in DELETE for joins
>
>   UPDATE already allows this (UPDATE...FROM) but we need similar
>   functionality in DELETE.  It's been agreed that the keyword should
>   be USING, to avoid anything as confusing as DELETE FROM a FROM b.

Modified Files:
--------------
    pgsql-server/doc:
        TODO (r1.1325 -> r1.1326)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql-server/doc/TODO.diff?r1=1.1325&r2=1.1326)