To inform users that they can use --regexp-ignore-case now, and that
existing scripts which relied on that + PCRE may be buggy. See 9e3cbc59d5 ("log: make --regexp-ignore-case work with --perl-regexp",
2017-05-20).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>