Drop BeatmapSet, only BeatmapSetInfo is necessary

osu.Game/Beatmaps/BeatmapSet.cs

@@ -1,19 +0,0 @@
-//Copyright (c) 2007-2016 ppy Pty Ltd <contact@ppy.sh>.
-//Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
-
-using System.Collections.Generic;
-using osu.Game.Database;
-using osu.Game.Users;
-
-namespace osu.Game.Beatmaps
-{
-    /// <summary>
-    /// A beatmap set contains multiple beatmap (difficulties).
-    /// </summary>
-    public class BeatmapSet
-    {
-        public BeatmapSetInfo BeatmapSetInfo { get; set; }
-        public List<Beatmap> Beatmaps { get; protected set; } = new List<Beatmap>();
-        public User Creator { get; set; }
-    }
-}

osu.Game/Database/BeatmapDatabase.cs

@@ -82,6 +82,11 @@ namespace osu.Game.Database
             return ArchiveReader.GetReader(storage, beatmapSet.Path);
         }
         
+        public BeatmapSetInfo GetBeatmapSet(int id)
+        {
+            return Query<BeatmapSetInfo>().Where(s => s.BeatmapSetID == id).FirstOrDefault();
+        }
+        
         public Beatmap GetBeatmap(BeatmapInfo beatmapInfo)
         {
             var beatmapSet = Query<BeatmapSetInfo>()

osu.Game/osu.Game.csproj

@@ -61,7 +61,6 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Beatmaps\Beatmap.cs" />
-    <Compile Include="Beatmaps\BeatmapSet.cs" />
     <Compile Include="Beatmaps\Objects\Catch\CatchConverter.cs" />
     <Compile Include="Beatmaps\Objects\Catch\Drawable\DrawableFruit.cs" />
     <Compile Include="Beatmaps\Objects\HitObject.cs" />