Add support for recording console output

This commit adds support for recording console output
as well as exporting it to either text or HTML. A user can
also provide their own encoder if they wish.

src/Spectre.Console/AnsiConsole.Recording.cs

@@ -0,0 +1,66 @@
+using System;
+
+namespace Spectre.Console
+{
+    /// <summary>
+    /// A console capable of writing ANSI escape sequences.
+    /// </summary>
+    public static partial class AnsiConsole
+    {
+        /// <summary>
+        /// Starts recording the console output.
+        /// </summary>
+        public static void Record()
+        {
+            _recorder = new Recorder(_console.Value);
+        }
+
+        /// <summary>
+        /// Exports all recorded console output as text.
+        /// </summary>
+        /// <returns>The recorded output as text.</returns>
+        public static string ExportText()
+        {
+            if (_recorder == null)
+            {
+                throw new InvalidOperationException("Cannot export text since a recording hasn't been started.");
+            }
+
+            return _recorder.ExportText();
+        }
+
+        /// <summary>
+        /// Exports all recorded console output as HTML.
+        /// </summary>
+        /// <returns>The recorded output as HTML.</returns>
+        public static string ExportHtml()
+        {
+            if (_recorder == null)
+            {
+                throw new InvalidOperationException("Cannot export HTML since a recording hasn't been started.");
+            }
+
+            return _recorder.ExportHtml();
+        }
+
+        /// <summary>
+        /// Exports all recorded console output using a custom encoder.
+        /// </summary>
+        /// <param name="encoder">The encoder to use.</param>
+        /// <returns>The recorded output.</returns>
+        public static string ExportCustom(IAnsiConsoleEncoder encoder)
+        {
+            if (_recorder == null)
+            {
+                throw new InvalidOperationException("Cannot export HTML since a recording hasn't been started.");
+            }
+
+            if (encoder is null)
+            {
+                throw new ArgumentNullException(nameof(encoder));
+            }
+
+            return _recorder.Export(encoder);
+        }
+    }
+}