obsolete: use new-style command registration

obsolete: make rebase abort with --keep obsolete modifies rebase to mark rebased changesets obsolete instead of stripping them, which makes --keep irrelevant.

obsolete: fix rebase wrapping ui and repo arguments were swapped which made --keep calls traceback.

obsolete: add debugsuccessors command It dumps obsolete changesets and their successors.

evolve: add alias for kill and stabilize

merge with 0.1.0 tag

Added tag 0.1.0 for changeset 6c6bb7a23bb5

stabilize: improve unstable selection heuristic Without argument, stabilize was picking the first in: "unstable() and ((suspended() or obsancestors(::.))::)" which usually returned the "oldest" unstable revision in parent predecessors descendants. This revision is interesting because it usually gives "soft" merges but rebasing it left the working directory on a remote branch, which was very confusing. The new heuristic picks an unstable changeset which can be rebased on top of the parent revision, or on top of one of its descendants (selected in revision order). This has the advantage of selecting a revision which can be rebased on the current subtree, and leave the working directory in a more convenient location.

amend: remove useless repo.changelog alias

README: some more changes