smartset: preserve istopo for baseset operations This is a follow-up of "smartset: use native set operations as fast paths". It's more correct to just preserve the "istopo" information for "&" and "-" operations, like what filteredset does.

record: update help to describe ui.interface hg help record was not accurate if using another interface than the text one

ui: replace obsolete default-push with default:pushurl (issue5485) Default-push has been deprecated in favour of default:pushurl. But "hg clone" still inserts this in every hgrc file it creates. This patch updates the message by replacing default-push with default:pushurl and also makes the necessary changes to test files.