reverse sense of return value from python hooks.
old scheme (False/None/0/'' == fail) made coding style
unnatural, did not allow use of mercurial commands as hooks.
new scheme (False/None/0 == pass) is pythonic, does not require peculiar
"return True" at ends of hooks, allows hooks like this:
[hooks]
# update working dir after push into this repo
changegroup.update = python:mercurial.commands.update
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
pulling from ../source
abort: pretxncommit hook exited with status 1
transaction abort!
rollback completed
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
(run 'hg update' to get a working copy)
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 2 changesets, 2 total revisions