More efficient and easy to understand yuv2buffer converter

[gordinmitya]

Hello, @owahltinez
I opened issue #277 so here is PR to full fill it. And as it was not only issue/question regarding YuvToRgbConverter hope this will help.

Documentation about approach, unit-tests, performance benchmarks + demo application are here https://github.com/gordinmitya/yuv2buf.

I compared performance of previous and new code on my Mi 9t pro (Snapdragon 855): old 3.5-4.0ms, new 2.6-3.0ms.
Modified CameraActivity.kt I used for comparison.

Will be happy to answer questions, if any!

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[gordinmitya]

@googlebot I signed it!

[gordinmitya]

@owahltinez could you take a look if you have time?
I would appreciate your feedback about this approach

[ggfan]

@gordinmitya could you access #399?