Merge branch 'sb/submodule-move-nested'

Moving a submodule that itself has submodule in it with "git mv"
forgot to make necessary adjustment to the nested sub-submodules;
now the codepath learned to recurse into the submodules.

* sb/submodule-move-nested:
  submodule: fixup nested submodules after moving the submodule
  submodule-config: remove submodule_from_cache
  submodule-config: add repository argument to submodule_from_{name, path}
  submodule-config: allow submodule_free to handle arbitrary repositories
  grep: remove "repo" arg from non-supporting funcs
  submodule.h: drop declaration of connect_work_tree_and_git_dir

submodule.h

@@ -105,7 +105,6 @@ extern int push_unpushed_submodules(struct oid_array *commits,
 				    const char **refspec, int refspec_nr,
 				    const struct string_list *push_options,
 				    int dry_run);
-extern void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir);
 /*
  * Given a submodule path (as in the index), return the repository
  * path of that submodule in 'buf'. Return -1 on error or when the