Report on push/pull if heads are merged, too, like for new heads.
Use case: If a remote repo has two heads and I _want_ to merge them, I merge
and push. Meanwhile someone else pushed on top of one of the heads. He won't
get a warning, because he doesn't create a new head, I won't notice that I
don't close a head, because I don't get a message telling me.
#!/bin/sh
set -e
mkdir test
cd test
echo foo>foo
hg init
hg addremove
hg commit -m "1"
hg verify
hg clone . ../branch
cd ../branch
hg co
echo bar>>foo
hg commit -m "2"
cd ../test
hg pull ../branch
hg verify
hg co
cat foo
hg manifest