fix the hud enabling/autohiding for new players

hud.lua

@@ -217,5 +217,8 @@ minetest.register_on_joinplayer(function(player)
 				quests.show_hud(playername)
 			end, playername)
 		end
+	else --new player
+		quests.hud[playername] = {autohide = true}
+		quests.active_quests[playername] = {}
 	end
 end)