"hg serve" proposal: add links to anchors within diff to file list so we can jump into the diff

[Peter Arrenbrecht]

In "hg serve"'s output for a changeset, you first get a list of
changed files, then the diff. But clicking a file shows the file, not
the diff. And the list does not tell me whether the files where
additions, removals, or changes. Something like diffstat would be
welcome here. And an additional link on the files that takes you to
the file's diff.

What do you people think? Any objections to my attempting this?

-peo