compat: temporarily move copies fix to compat.py This patch moves a fixed version of copies._fullcopytracing() to compat.py as this was not fixed in core before release and also we need to do this anyway for the older versions of mercurial. This fix is that when base changeset is not ancestor of any of the merging commits, we don't throw an error. The phabricator differential which will fix this in core is https://phab.mercurial-scm.org/D3896. This fixes the traceback we get in previous changeset while relocating one of the content-divergent changeset.

evolve: continue conflicted relocation content-divergence This patch adds logic to continue an conflicted content-divergence resolution which was interrupted while relocating one of the divergent commits. The tests shows the there is some mishandling of copies internally which will be fixed in next patch.

topic: use self instead of repo in topicrepo methods Referring to repo here was somehow preventing it from being garbage-collected (important in hgweb, where currently every request gets a new repo).

evolvecmd: introduce fn to be wrapped by extensions resolving content-div The function added will be used by extension by wrapping it and adding logic to merge data introduced by them. For example: topic extension can wrap this function and add logic to merge topic names.

evolvecmd: move remaining logic to merge commit desc to existing utility fn This was a bit awful because we had a utility function and still we did some of merging outside of that fn. So let's move the remaining parts there.

amend: allow aborting an `amend --patch` by saving an empty file (issue5925) This patch fixes issue5925 by allow aborting a `hg amend --patch` call by saving an empty patch file. This is similar to aborting of `hg amend` when commit message is empty. Test changes demonstrate the fix.

tests: add a test to demonstrate issue5925 The issue will be fixed in next patch.

test: fix possible output change from 4.7 Change in debug timing can display these extra messages.