[tldoc] Russian translation update

[Karl Berry]

Hi Vladimir,

    Small update (I notice wrong string in ru.po taken from svn).

I installed it, thanks.

    Also there were two messages from Karl Berry and Hans Hagen about
    program translation, then is it so neccessary to
    translate paper sizes? 
    
Norbert and I were not sure.

    There are two strings: 'a4' and 'letter'.  AFAIK 'A4' is standard
    name (according to wikipedia, this name in ISO216) and 'letter'
    though isn't widely used in Russian but also a "standard" name.

The question is not what the ISO says.  The question is what people
really do in practice.  If people in non-English countries generally
prefer the English strings "a4" and "letter" for paper sizes, sure, of
course we can make them untranslatable.

If a Chinese person is writing about paper sizes, for example, do they
really use those English strings?  Seems surprising to me.

Thanks,
karl