Upon pull or unbundle, we display a message with the range of new revisions
fetched. This revision range could readily be used after a pull to look out
what's new with 'hg log'. The algorithm takes care of filtering "obsolete"
revisions that might be present in transaction's "changes" but should not be
displayed to the end user.
While it should be safe to switch to the new manifest format on an
existing repo, let's keep it simple for now and make the configuration
have any effect only at repo creation time. If the configuration is
enabled then (at repo creation), we add an entry to requires and read
that instead of the configuration from then on.
