Currently VideoReader color conversion:

1. Forces quantization to 8 bits by using the NV12 surface format for all inputs regardless of the encoded bit depth or chroma subsampling.
2. Does not respect the color space standard if specified in the video source.
3. Only outputs BGR, BGRA, GRAY and NV12 frames.

Note: Previous attempts to fix this #3468 didn't address (2).

This PR uses the Nvidia Video Codec SDK ColorSpace.cu sample as a guide to:

1. Use the color space standard if it exists and default back to a suitable format based on the video resolution if not.
2. Decode YUV420 10/12 bit and YUV444 8/10/12 bit sources.
3. Allow the user to choose the desired output bitdepth. e.g. Reqest 8 bit output from a 16 bit source.
4. Add RGB/RGBA and planar outputs.

Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

• I agree to contribute to the project under Apache 2 License.
• To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
• The PR is proposed to the proper branch
• There is a reference to the original bug report and related work
• There is accuracy test, performance test and test data in opencv_extra repository, if applicable
  Patch to opencv_extra has the same branch name.
• The feature is well documented and sample code can be built with the project CMake