obsnote: warn if user try to store a note in obsmarker on an older hg Support to store a note in obsmarker is from hg>=4.4. We have added notes support to all the evolve commands but we do support versions which don't support storing note in obsmarker. Warn if user tries to store a note in older hg.

topic: use 'hookargs' over 'tr.changes' for flow control The 'tr.changes' attribute do not exists until 4.2.

topic: move function wrapping from reposetup to uisetup Having the function un reposetup means they get wrapped over and over again for long lived process.