debugdiscovery: add flags to run discovery on subsets of the local repo
Generating new repository using strip of local clone is very expensive for large
repositories. And such large repository are the most likely to requires
debugging around discovery. So we add a simple way to run discovery using
provided sets of heads.
Differential Revision: https://phab.mercurial-scm.org/D9945
== New Features ==
* `hg purge` is now a core command using `--confirm` by default.
* The `rev-branch-cache` is now updated incrementally whenever changesets
are added.
== New Experimental Features ==
* `hg diff` now takes an experimental `--merge` flag which causes `hg
diff --change` to show the changes relative to an automerge for
merge changesets. This makes it easier to detect and review manual
changes performed in merge changesets.
== Bug Fixes ==
== Backwards Compatibility Changes ==
== Internal API Changes ==
* `changelog.branchinfo` is deprecated and will be removed after 5.8.
It is superseded by `changelogrevision.branchinfo`.