Rectangle parameters changed to float

- Some examples tweaks
- Reviewed ImageFormat()
- Use float for text fontSize

examples/core/core_3d_camera_free.c

@@ -21,7 +21,7 @@ int main()
     InitWindow(screenWidth, screenHeight, "raylib [core] example - 3d camera free");
 
     // Define the camera to look into our 3d world
-    Camera camera;
+    Camera3D camera;
     camera.position = (Vector3){ 10.0f, 10.0f, 10.0f }; // Camera position
     camera.target = (Vector3){ 0.0f, 0.0f, 0.0f };      // Camera looking at point
     camera.up = (Vector3){ 0.0f, 1.0f, 0.0f };          // Camera up vector (rotation towards target)