[Bizgres-general] Commit - bitmap scan and partitioning

[Luke Lonergan]

I've committed Tom's bitmap scan (ported by Jie Zhang) and Simon's
partitioning part 1 (constraint exclusion) to the bizgres tip.  Constraint
exclusion is on by default.

Also in the CVS tip are the first checkins for KETL (thanks to KNI and Nick
Wakefield) and JasperReports (thanks to Barry Klawans of Jaspersoft).

We're initiating testing now for release next week.

- Luke