Merge branch 'maint' into bc/master-diff-hunk-header-fix

* maint: (41 commits)
  Clarify commit error message for unmerged files
  Use strchrnul() instead of strchr() plus manual workaround
  Use remove_path from dir.c instead of own implementation
  Add remove_path: a function to remove as much as possible of a path
  git-submodule: Fix "Unable to checkout" for the initial 'update'
  Clarify how the user can satisfy stash's 'dirty state' check.
  Remove empty directories in recursive merge
  Documentation: clarify the details of overriding LESS via core.pager
  Update release notes for 1.6.0.3
  checkout: Do not show local changes when in quiet mode
  for-each-ref: Fix --format=%(subject) for log message without newlines
  git-stash.sh: don't default to refs/stash if invalid ref supplied
  maint: check return of split_cmdline to avoid bad config strings
  builtin-prune.c: prune temporary packs in <object_dir>/pack directory
  Do not perform cross-directory renames when creating packs
  Use dashless git commands in setgitperms.perl
  git-remote: do not use user input in a printf format string
  make "git remote" report multiple URLs
  Start draft release notes for 1.6.0.3
  git-repack uses --no-repack-object, not --no-repack-delta.
  ...

Conflicts:
	RelNotes

builtin-commit.c

@@ -639,7 +639,7 @@ static int prepare_to_commit(const char *index_file, const char *prefix)
 		active_cache_tree = cache_tree();
 	if (cache_tree_update(active_cache_tree,
 			      active_cache, active_nr, 0, 0) < 0) {
-		error("Error building trees");
+		error("Error building trees; the index is unmerged?");
 		return 0;
 	}