Add initial prototype.

3-mid/opengl/source/lean/buffer/opengl-buffer-texture_coords.ads

@@ -0,0 +1,7 @@
+with
+     openGL.Buffer.general;
+
+package openGL.Buffer.texture_coords is new openGL.Buffer.general (base_Object   => Buffer.array_Object,
+                                                                   Index         => Index_t,
+                                                                   Element       => Coordinate_2D,
+                                                                   Element_Array => Coordinates_2D);