Merge branch 'ps/environ-wo-the-repository'

Code clean-up.

* ps/environ-wo-the-repository: (21 commits)
  environment: stop storing "core.notesRef" globally
  environment: stop storing "core.warnAmbiguousRefs" globally
  environment: stop storing "core.preferSymlinkRefs" globally
  environment: stop storing "core.logAllRefUpdates" globally
  refs: stop modifying global `log_all_ref_updates` variable
  branch: stop modifying `log_all_ref_updates` variable
  repo-settings: track defaults close to `struct repo_settings`
  repo-settings: split out declarations into a standalone header
  environment: guard state depending on a repository
  environment: reorder header to split out `the_repository`-free section
  environment: move `set_git_dir()` and related into setup layer
  environment: make `get_git_namespace()` self-contained
  environment: move object database functions into object layer
  config: make dependency on repo in `read_early_config()` explicit
  config: document `read_early_config()` and `read_very_early_config()`
  environment: make `get_git_work_tree()` accept a repository
  environment: make `get_graft_file()` accept a repository
  environment: make `get_index_file()` accept a repository
  environment: make `get_object_directory()` accept a repository
  environment: make `get_git_common_dir()` accept a repository
  ...

builtin/pack-objects.c

@@ -3968,7 +3968,7 @@ static int add_loose_object(const struct object_id *oid, const char *path,
  */
 static void add_unreachable_loose_objects(void)
 {
-	for_each_loose_file_in_objdir(get_object_directory(),
+	for_each_loose_file_in_objdir(repo_get_object_directory(the_repository),
 				      add_loose_object,
 				      NULL, NULL, NULL);
 }