added ratings to examples

examples/models/models_orthographic_projection.c

@@ -2,6 +2,8 @@
 *
 *   raylib [models] example - Show the difference between perspective and orthographic projection
 *
+*   Example complexity rating: [★☆☆☆] 1/4
+*
 *   Example originally created with raylib 2.0, last time updated with raylib 3.7
 *
 *   Example contributed by Max Danielsson (@autious) and reviewed by Ramon Santamaria (@raysan5)