Add ModuleBase and EmbedBuilder docfx

src/Discord.Net.Commands/ModuleBase.cs

@@ -21,11 +21,16 @@ namespace Discord.Commands
         {
             return await Context.Channel.SendMessageAsync(message, isTTS, embed, options).ConfigureAwait(false);
         }
-
+        /// <summary>
+        /// The method to execute before executing the command.
+        /// </summary>
         protected virtual void BeforeExecute(CommandInfo command)
         {
         }
-
+        /// <summary>
+        /// The method to execute after executing the command.
+        /// </summary>
+        /// <param name="command"></param>
         protected virtual void AfterExecute(CommandInfo command)
         {
         }

src/Discord.Net.Core/Entities/Messages/EmbedBuilder.cs

@@ -4,6 +4,9 @@ using System.Collections.Immutable;
 
 namespace Discord
 {
+    /// <summary>
+    /// Builder for creating an <see cref="Embed"/> to be sent.
+    /// </summary>
     public class EmbedBuilder
     {
         private readonly Embed _embed;