Added missing files

src/Discord.Net/Events/BanEventArgs.cs

@@ -0,0 +1,16 @@
+using System;
+
+namespace Discord
+{
+    public class BanEventArgs : EventArgs
+    {
+        public Server Server { get; }
+        public ulong UserId { get; }
+
+        public BanEventArgs(Server server, ulong userId)
+        {
+            Server = server;
+            UserId = userId;
+        }
+    }
+}

src/Discord.Net/Extensions.cs

@@ -0,0 +1,37 @@
+using System;
+using System.Collections.Concurrent;
+using System.Globalization;
+using System.Runtime.CompilerServices;
+
+namespace Discord
+{
+    internal static class InternalExtensions
+    {
+		internal static readonly IFormatProvider _format = CultureInfo.InvariantCulture;
+		
+		public static ulong ToId(this string value)
+			=> ulong.Parse(value, NumberStyles.None, _format);
+		public static ulong? ToNullableId(this string value)
+			=> value == null ? (ulong?)null : ulong.Parse(value, NumberStyles.None, _format);
+		
+		public static string ToIdString(this ulong value)
+			=> value.ToString(_format);
+		public static string ToIdString(this ulong? value)
+			=> value?.ToString(_format);
+        
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static bool HasBit(this uint value, byte bit) => ((value >> bit) & 1U) == 1;
+
+        public static bool TryGetAdd<TKey, TValue>(this ConcurrentDictionary<TKey, TValue> d, 
+            TKey key, Func<TKey, TValue> factory, out TValue result)
+        {
+            while (true)
+            {
+                if (d.TryGetValue(key, out result))
+                    return false;
+                if (d.TryAdd(key, factory(key)))
+                    return true;
+            }
+        }
+    }
+}