Copyright-holder and year information is extracted from git log.
git history begins in 2005. So (C) from 1998..2005 is lost. Also some
(C) assignment of commits where the committer didn't use --author.
This allows correct reordering of the mixer "track_model" even
when non-route elements are present.
This isn't really utilized in the Editor at present because we do
not show VCAs there at all, but it will become important in the
future when we represent VCA automation there