Merge branch 'jc/stream-to-pack'

* jc/stream-to-pack:
  bulk-checkin: replace fast-import based implementation
  csum-file: introduce sha1file_checkpoint
  finish_tmp_packfile(): a helper function
  create_tmp_packfile(): a helper function
  write_pack_header(): a helper function

Conflicts:
	pack.h

environment.c

@@ -62,6 +62,7 @@ int grafts_replace_parents = 1;
 int core_apply_sparse_checkout;
 int merge_log_config = -1;
 struct startup_info *startup_info;
+unsigned long pack_size_limit_cfg;
 
 /* Parallel index stat data preload? */
 int core_preload_index = 0;