Streebog hash algorithm

A part of the library containing only Streebog (GOST R 34.11-2012) algorithm, taken from the one published here. IDK if someone needs this, but let it be here.

Alharytm hashavańnia Streebog

Častka biblijateky, jakaja źmiaščaje toĺki alharytm Streebog (GOST R 34.11-2012), uziataja z apublikavanaj tut biblijateki. Nia viedaju, ci patrebna to kamuś, alie chaj budzie tut.