FIrst pass on adding export command

Commands/ExportCommand.cs

@@ -0,0 +1,73 @@
+namespace twot
+{
+    using System;
+    using System.Collections.Generic;
+    using System.CommandLine;
+    using System.CommandLine.Invocation;
+    using System.Threading.Tasks;
+    using Tweetinvi;
+    using Tweetinvi.Models;
+    using static System.ConsoleColor;
+    using static CommandHelpers;
+    using static ConsoleHelper;
+
+#pragma warning disable CA1812
+    internal class ExportCommand : ICommand
+#pragma warning restore CA1812
+    {
+        public void AddCommand(Command rootCommand)
+        {
+            var cmd = new Command("Export", "Exports your block or mute list");
+            cmd.AddAlias("export");
+            cmd.AddAlias("e");
+
+            var muteOption = new Option<bool>("--mute", "Rather than export your block list, this command will " +
+                "export your mute list");
+            muteOption.AddAlias("-m");
+            cmd.Add(muteOption);
+
+            var fileOption = new Option<string>("--file", () => "export.log", "The file to export to. Defaults to " +
+                "export.log");
+            fileOption.AddAlias("-f");
+            cmd.Add(fileOption);
+
+            cmd.Handler = CommandHandler.Create<bool, string>(this.Execute);
+            rootCommand.Add(cmd);
+        }
+
+        private async Task<int> Execute(bool mute, string file)
+        {
+            if (!CommandHeader("Running export ✍", false))
+            {
+                return -1;
+            }
+
+            using (var logger = new ThreadedLogger($"{file}", true))
+            using (var spinner = new Spinner())
+            {
+                logger.LogMessage($"# Export started {DateTime.Now.ToLongDateString()} " +
+                    $"{DateTime.Now.ToLongTimeString()}");
+                logger.LogMessage($"# {(mute ? "Muted accounts" : "Blocked accounts")}");
+
+                var me = User.GetAuthenticatedUser();
+                IEnumerable<IUser> users;
+                if (mute)
+                {
+                    users = Account.GetMutedUsers();
+                }
+                else
+                {
+                    users = await me.GetBlockedUsersAsync();
+                }
+
+                foreach (var user in users)
+                {
+                    logger.LogMessage(user.ScreenName);
+                }
+            }
+
+            Writeln(Green, "Export completed");
+            return 0;
+        }
+    }
+}