Editing of more reference pages.

doc/src/sgml/ref/abort.sgml

doc/src/sgml/ref/deallocate.sgml

doc/src/sgml/ref/delete.sgml

doc/src/sgml/ref/end.sgml

doc/src/sgml/ref/execute.sgml

doc/src/sgml/ref/explain.sgml

doc/src/sgml/ref/grant.sgml

doc/src/sgml/ref/insert.sgml

doc/src/sgml/ref/listen.sgml

doc/src/sgml/ref/load.sgml

doc/src/sgml/ref/lock.sgml

doc/src/sgml/ref/notify.sgml

doc/src/sgml/ref/prepare.sgml

doc/src/sgml/ref/reindex.sgml

doc/src/sgml/ref/revoke.sgml

doc/src/sgml/ref/rollback.sgml

doc/src/sgml/ref/start_transaction.sgml

doc/src/sgml/ref/truncate.sgml

doc/src/sgml/ref/unlisten.sgml

doc/src/sgml/ref/update.sgml