test-revert: add case for nothing changed

dispatch: set descriptors on the request repo.ui

dispatch: pass the correct ui to runcommand For commands that take a repo, repo.ui is passed as the ui to runcommand. This restores that behaviour when the request has a repo.

archive: wrap the ui descriptor so it doesn't get closed archival.tarit closes the fileobj if one is passed to it, which is undesired when reading from '-'.

transplant: use ui out descriptor when calling util.system

bisect: use ui out descriptor when calling util.system

extdiff: use ui out descriptor when calling util.system

ui: use ui out descriptor when calling util.system

call reposetup for repositories returned from peer (issue2864) Extension setup functions were not being called when repositories were obtained using the peer function instead of the repository function.

tests: solaris [ doesn't know -e