Add new display for timing row attributes

osu.Game/Beatmaps/Timing/TimeSignatures.cs

@@ -1,11 +1,16 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System.ComponentModel;
+
 namespace osu.Game.Beatmaps.Timing
 {
     public enum TimeSignatures
     {
+        [Description("4/4")]
         SimpleQuadruple = 4,
+
+        [Description("3/4")]
         SimpleTriple = 3
     }
 }