hgweb: show users recorded in obsolescence markers
It's useful to see who obsoleted a commit, because it's not always done by its
author (hg-committed is a good example, because people rebase stacks of commits
made by various people).
Usernames are obfuscated, but look correct (e.g. "test" is
"test").
graft c-ext
graft zstd
include make_cffi.py
include setup_zstd.py
include zstd.c