documentation of pg_select command.

Laser.

Please check compile errors before you commit!

member offset.

per bug report from Stefan Hadjistoytchev.  There are some cases
where the dot notation works, but there are more where it doesn't.
Eventually ought to consider fixing the parser to allow cases like
func().field, but for now this is the simplest patch.

laser

Thanks.

Teodor Sigaev

  Editing pass over entire chapter
  Rewrote section dealing with Large Objects to also talk about bytea support
  Removed secion on Serialize functionality a we intend to remove it in the
   next release