hugely optimized by scaling the bw image for each window size, and more timers

src/visualhaar.rs

@@ -386,7 +386,7 @@ impl HaarClassifier {
                 &img_bw, 
                 (img_bw.width() as f64 / scale + 1.) as u32, 
                 (img_bw.height() as f64 / scale + 1.) as u32, 
-                image::imageops::FilterType::Nearest
+                image::imageops::FilterType::CatmullRom
             );
 
             let integral = Self::integral_image(&img_bw_scaled);