Update Russian translation

[valery-kirichenko]

Please also consider adding support for grammatical numbers. For example, in Russian there are 3 forms of word "файл" (file), we say "1 файл", "2 файла" (from 2 to 4), "5 файлов" (from 5 to 9 and 0), "21 файл" (same thing with the last digit), "22 файла", "25 файлов". So the form of a word depends on the number before it a bit more than just one or multiple as it is in English.
As for now I covered only 2 of 3 forms using brackets.

[vktr]

Thanks for the PR! Regarding grammatical numbers - it would add a lot of complexity since not every language follows the same standard (Swedish has only two forms). I'll see if I can figure something out, but I don't see it happening in the near future, sorry.