Add GetSeasonalBackgroundsRequest

osu.Game/Online/API/Requests/Responses/APISeasonalBackgrounds.cs

@@ -0,0 +1,20 @@
+// 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.Collections.Generic;
+using Newtonsoft.Json;
+
+namespace osu.Game.Online.API.Requests.Responses
+{
+    public class APISeasonalBackgrounds
+    {
+        [JsonProperty("backgrounds")]
+        public List<APISeasonalBackground> Backgrounds { get; set; }
+    }
+
+    public class APISeasonalBackground
+    {
+        [JsonProperty("url")]
+        public string Url { get; set; }
+    }
+}