Add FIGlet text support

Closes #97

src/Spectre.Console/Extensions/FigletTextExtensions.cs

@@ -0,0 +1,27 @@
+using System;
+
+namespace Spectre.Console
+{
+    /// <summary>
+    /// Contains extension methods for <see cref="FigletText"/>.
+    /// </summary>
+    public static class FigletTextExtensions
+    {
+        /// <summary>
+        /// Sets the color of the FIGlet text.
+        /// </summary>
+        /// <param name="text">The text.</param>
+        /// <param name="color">The color.</param>
+        /// <returns>The same instance so that multiple calls can be chained.</returns>
+        public static FigletText Color(this FigletText text, Color? color)
+        {
+            if (text is null)
+            {
+                throw new ArgumentNullException(nameof(text));
+            }
+
+            text.Color = color ?? Console.Color.Default;
+            return text;
+        }
+    }
+}