add [Socket/Rest]NewsChannel types

src/Discord.Net.Rest/Entities/Channels/RestNewsChannel.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Model = Discord.API.Channel;
+
+namespace Discord.Rest
+{
+    /// <summary>
+    ///     Represents a REST-based news channel in a guild that has the same properties as a <see cref="RestTextChannel"/>.
+    /// </summary>
+    [DebuggerDisplay(@"{DebuggerDisplay,nq}")]
+    public class RestNewsChannel : RestTextChannel
+    {
+        internal RestNewsChannel(BaseDiscordClient discord, IGuild guild, ulong id)
+            :base(discord, guild, id)
+        {
+        }
+        internal new static RestNewsChannel Create(BaseDiscordClient discord, IGuild guild, Model model)
+        {
+            var entity = new RestNewsChannel(discord, guild, model.Id);
+            entity.Update(model);
+            return entity;
+        }
+    }
+}

src/Discord.Net.WebSocket/Entities/Channels/SocketNewsChannel.cs

@@ -0,0 +1,23 @@
+using System.Diagnostics;
+using Model = Discord.API.Channel;
+
+namespace Discord.WebSocket
+{
+    /// <summary>
+    ///     Represents a WebSocket-based news channel in a guild that has the same properties as a <see cref="RestTextChannel"/>.
+    /// </summary>
+    [DebuggerDisplay(@"{DebuggerDisplay,nq}")]
+    public class SocketNewsChannel : SocketTextChannel
+    {
+        internal SocketNewsChannel(DiscordSocketClient discord, ulong id, SocketGuild guild)
+            :base(discord, id, guild)
+        {
+        }
+        internal new static SocketTextChannel Create(SocketGuild guild, ClientState state, Model model)
+        {
+            var entity = new SocketNewsChannel(guild.Discord, model.Id, guild);
+            entity.Update(state, model);
+            return entity;
+        }
+    }
+}