raise util.Abort instead of assertion when trying to evolve a merge changeset. This prevent exposing a nasty traceback to the user.

merge with stable

tutorial: fix note We need a double semin colon, otherwise this is a comment.

tutorial: warn about rollback beeing obsolete

tutorial: use grab instead of rebase. grab as now the advantage to move the working directory.

tutorial Clarify "." explanation

tutorial: update divergent changeset section Still not there but less fuzy.

tutorial: use long form of argument for the sake of clarity

tutorial: fix some various typo

tutorial Display the help of appropriate command in section that need writting