ggml : add Q8_0 quantization for intermediate results (#951)
* ggml : add Q8_0 quantization for intermediate results
* quantize-stats : fix test + add it to Makefile default
* Q8: use int8_t, AVX/AVX2 optimizations
* ggml : fix quantize_row_q8_0() ARM_NEON rounding
* minor : updates after rebase to latest master
* quantize-stats : delete obsolete strings
* ggml : fix q4_1 dot func
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Co-authored-by: Stephan Walter <stephan@walter.name>
