In a subsequent commit, we will add configuration options that are
specific to each kind of object filter, in which case it is handy to
have a function that translates between 'enum
list_objects_filter_choice' and an appropriate configuration-friendly
string.
Signed-off-by: Taylor Blau <me@ttaylorr.com> Acked-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>