dlib 0.21.0 beta1

• dlib.text
  • Breaking change: deprecated module dlib.text.unmanagedstring has been removed
  • Breaking change: deprecated method String.byDChar has been removed
  • UTF16Decoder and UTF16Encoder are deprecated, use UTF16LEDecoder and UTF16LEEncoder instead
• dlib.image
  • Breaking change: deprecated module dlib.image.io.io has been removed
  • load and save are deprecated, use loadImage and saveImage instead
  • loadAnimated and saveAnimated are deprecated, use loadAnimatedImage and saveAnimatedImage instead
  • loadHDRI and saveHDRI are deprecated, use loadHDRImage and saveHDRImage instead
  • Fix integer overflow in Image.getPixel and Image.setPixel
• dlib.container
  • Breaking change: deprecated alias DynamicArray has been removed
• dlib.coding
  • Breaking change: deprecated module dlib.coding.hash has been removed
• dlib.audio
  • load and save are deprecated, use loadSound and saveSound instead
• dlib.serialization
  • Fix a bug in JSON decoder
• Misc
  • Switched from Travis CI to GitHub Actions for running integration tests.