refactor: put enums in separate files and add new scanner state and detection speed.

 library mobile_scanner;
 
+export 'src/enums/camera_facing.dart';
+export 'src/enums/detection_speed.dart';
+export 'src/enums/mobile_scanner_state.dart';
+export 'src/enums/ratio.dart';
+export 'src/enums/torch_state.dart';
 export 'src/mobile_scanner.dart';
 export 'src/mobile_scanner_arguments.dart';
 export 'src/mobile_scanner_controller.dart';

@@ -5,7 +5,7 @@ import 'dart:ui' as ui;
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_web_plugins/flutter_web_plugins.dart';
-import 'package:mobile_scanner/mobile_scanner.dart';
+import 'package:mobile_scanner/src/enums/camera_facing.dart';
 import 'package:mobile_scanner/src/web/jsqr.dart';
 import 'package:mobile_scanner/src/web/media.dart';
 

+/// The facing of a camera.
+enum CameraFacing {
+  /// Front facing camera.
+  front,
+
+  /// Back facing camera.
+  back,
+}

+/// The detection speed of the scanner.
+enum DetectionSpeed {
+
+  /// The scanner will only scan a barcode once, and never again until another
+  /// barcode has been scanned.
+  noDuplicates,
+
+  /// Front facing camera.
+  normal,
+
+  /// Back facing camera.
+  unrestricted,
+}

+enum MobileScannerState { undetermined, authorized, denied }

+enum Ratio { ratio_4_3, ratio_16_9 }

+/// The state of torch.
+enum TorchState {
+  /// Torch is off.
+  off,
+
+  /// Torch is on.
+  on,
+}

@@ -2,8 +2,6 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:mobile_scanner/mobile_scanner.dart';
 
-enum Ratio { ratio_4_3, ratio_16_9 }
-
 /// A widget showing a live camera preview.
 class MobileScanner extends StatefulWidget {
   /// The controller of the camera.

@@ -7,28 +7,6 @@ import 'package:flutter/services.dart';
 import 'package:mobile_scanner/mobile_scanner.dart';
 import 'package:mobile_scanner/src/objects/barcode_utility.dart';
 
-/// The facing of a camera.
-enum CameraFacing {
-  /// Front facing camera.
-  front,
-
-  /// Back facing camera.
-  back,
-}
-
-enum MobileScannerState { undetermined, authorized, denied }
-
-/// The state of torch.
-enum TorchState {
-  /// Torch is off.
-  off,
-
-  /// Torch is on.
-  on,
-}
-
-// enum AnalyzeMode { none, barcode }
-
 class MobileScannerController {
   MethodChannel methodChannel =
       const MethodChannel('dev.steenbakker.mobile_scanner/scanner/method');