Support for Shape Detection API

[thijstriemstra]

"The interfaces of all three detectors, the FaceDetector, the BarcodeDetector, and the TextDetector, are very similar. They all provide a single asynchronous method detect that takes an ImageBitmapSource as an input (that is, either a CanvasImageSource, a Blob, or ImageData)."

See https://developers.google.com/web/updates/2019/01/shape-detection

Support for this API is dependant on hardware acceleration features that vary by operating system:

• BarcodeDetector: Android*, macOS (improved accuracy in 10.13+)
• FaceDetector: Android, macOS (improved accuracy in 10.13+), Windows 10
• TextDetector: Android*, macOS 10.11+, Windows 10

[thijstriemstra]

Started a branch at https://github.com/collab-project/videojs-record/tree/shape-detect-327