Add ScreenEditor and Screen class

src/app/zelda3/screen.cc

@@ -0,0 +1 @@
+#include "screen.h"

src/app/zelda3/screen.h

@@ -0,0 +1,21 @@
+#ifndef YAZE_APP_ZELDA3_SCREEN_H
+#define YAZE_APP_ZELDA3_SCREEN_H
+
+#include "app/gfx/bitmap.h"
+
+namespace yaze {
+namespace app {
+namespace zelda3 {
+
+class Screen {
+ public:
+  Screen() = default;
+
+ private:
+  gfx::Bitmap screen;
+  uchar *data = nullptr;
+};
+
+}  // namespace zelda3
+}  // namespace app
+}  // namespace yaze