Add Color record struct, small refactor, create a DaggerFramework.SceneGraph namespace.

Source/SceneGraph/Entities/Text2d.cs

@@ -0,0 +1,21 @@
+using DaggerFramework.Rendering;
+using System.Drawing;
+
+namespace DaggerFramework.SceneGraph
+{
+    public class Text2d : Drawable2d
+    {
+        public string Contents { get => _contents; set => _contents = value; }
+        public int FontSize { get => _fontSize; set => _fontSize = value; }
+        public Color FontColor { get => _fontColor; set => _fontColor = value; }
+
+        public override void OnDraw(Renderer renderer)
+        {
+            renderer.DrawDebugText(Position, _contents, _fontSize, _fontColor);
+        }
+
+        private string _contents = string.Empty;
+        private int _fontSize = 16;
+        private Color _fontColor = Color.White;
+    }
+}