Most of the callers have string_lists available already, whereas two
of them had to read data out of a string_list into an array of strings
just to call this function. So change repack_without_refs() to take
the list of refnames to omit as a string_list, and change the callers
accordingly.
Suggested-by: NRonnie Sahlberg <sahlberg@google.com>
Signed-off-by: NMichael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>