feat(docs): added barcode-mask link (#2128) [skip ci]

docs/RNCamera.md

@@ -499,7 +499,8 @@ Supported options:
     - `ios` Specifies capture settings suitable for CIF quality (352x288 pixel) video output.
     - `android` Not supported.
 
-- `videoBitrate`. (int greater than 0) This option specifies a desired video bitrate.  For example, 5\*1000\*1000 would be 5Mbps.
+- `videoBitrate`. (int greater than 0) This option specifies a desired video bitrate. For example, 5\*1000\*1000 would be 5Mbps.
+
   - `ios` Not supported.
   - `android` Supported.
 
@@ -561,6 +562,14 @@ iOS only. Returns a promise. The promise will be fulfilled with a boolean indica
 
 This component supports subviews, so if you wish to use the camera view as a background or if you want to layout buttons/images/etc. inside the camera then you can do that.
 
+**Example subview:**
+
+### react-native-barcode-mask
+
+A Barcode and QR code UI mask which can be use to render a scanning layout on camera with customizable styling.
+
+Read more about [react-native-barcode-mask](https://github.com/shahnawaz/react-native-barcode-mask) here.
+
 ## Testing
 
 To learn about how to test components which uses `RNCamera` check its [documentation about testing](./tests.md).
@@ -569,7 +578,6 @@ To learn about how to test components which uses `RNCamera` check its [documenta
 
 To see more of the `RNCamera` in action you can check out the [RNCamera examples directory](https://github.com/react-native-community/react-native-camera/tree/master/examples).
 
-
 ## Open Collective
 
 We are just beginning a funding campaign for react-native-camera. Contributions are greatly appreciated. When we gain more than \$250 we will begin distributing funds to core maintainers in a fully transparent manner. Feedback for this process is welcomed, we will continue to evolve the strategy as we grow and learn more.