Git 2.20.4

1. d99ea5f khash: silence -Wunused-function for delta-islands by Carlo Marcelo Arenas Belón · 7 years ago
2. 9249ca2 khash: factor out kh_release_* by René Scharfe · 7 years ago
3. ef3ca95 Add missing includes and forward declarations by Elijah Newren · 7 years ago
4. b32fa95 convert trivial cases to ALLOC_ARRAY by Jeff King · 10 years ago
5. 2756ca4 use REALLOC_ARRAY for changing the allocation size of arrays by René Scharfe · 11 years ago
6. 039dc71 hashmap: factor out getting a hash code from a SHA1 by Karsten Blees · 11 years ago
7. fff4275 pack-bitmap: add support for bitmap indexes by Vicent Marti · 12 years ago