Refactor ResourceLoader, use only Texture2d in Renderer.

Source/Resources/Loaders/Texture2dLoader.cs

@@ -0,0 +1,22 @@
+using StbImageSharp;
+
+namespace DaggerFramework
+{
+    public class Texture2dLoader : ResourceLoader<Texture2d>
+    {
+        public override Texture2d Load(string path)
+        {
+            ImageResult image;
+            using (var stream = File.OpenRead(path))
+            {
+                image = ImageResult.FromStream(stream, ColorComponents.RedGreenBlueAlpha);
+            }
+
+            Texture2d result = new Texture2d(path, image.Data);
+            result.Width = image.Width;
+            result.Height = image.Height;
+
+            return result;
+        }
+    }
+}