Merge branch 'lt/objlist' into next

* lt/objlist:
  Add "named object array" concept
  xdiff: minor changes to match libxdiff-0.21
  fix rfc2047 formatter.
  Fix t8001-annotate and t8002-blame for ActiveState Perl
  Add specialized object allocator

diff --cc Makefile
Simple merge

diff --cc diff-lib.c
Simple merge

diff --cc http-push.c
Simple merge