add example usage

README.md

@@ -5,3 +5,32 @@ This is a port of the ZXing (https://github.com/zxing/zxing) java barcode librar
 Porting of the testing library is incomplete.
 
 Porting was done with the rust language in mind, though some parts may resemble java more directly than a proper clean-sheet rust implementation.
+
+```
+use std::{collections::HashMap, rc::Rc};
+
+use rxing::multi::MultipleBarcodeReader;
+
+use image;
+
+use rxing;
+
+fn main() {
+    let file_name = "test_image.jpeg";
+
+    let img = image::open(file_name).unwrap();
+
+    let multi_format_reader = rxing::MultiFormatReader::default();
+    let mut scanner = rxing::multi::GenericMultipleBarcodeReader::new(multi_format_reader);
+    let results = scanner.decodeMultipleWithHints(
+        &rxing::BinaryBitmap::new(Rc::new(rxing::common::HybridBinarizer::new(Box::new(
+            rxing::BufferedImageLuminanceSource::new(img),
+        )))),
+        &HashMap::new(),
+    ).expect("decodes");
+
+    for result in results {
+        println!("{} -> {}",result.getBarcodeFormat(), result.getText())
+    }
+}
+```