Merge branch 'lv/status-say-working-tree-not-directory' into maint

"git status" used to say "working directory" when it meant "working
tree".

* lv/status-say-working-tree-not-directory:
  Use "working tree" instead of "working directory" for git status

wt-status.c

@@ -1554,7 +1554,7 @@ void wt_status_print(struct wt_status *s)
 			else
 				printf(_("nothing to commit\n"));
 		} else
-			printf(_("nothing to commit, working directory clean\n"));
+			printf(_("nothing to commit, working tree clean\n"));
 	}
 }