src/unistd.h ignored

This is a (generated) dummy file, that is needed for compiling files
that are generated with flex under Windows 95/NT.
TranslatorJapaneseEn and TranslatorKoreanEn converted to UTF-8

Actually, the translator_je.h and translator_ke.h use only ASCII
characters. The idLanguageCharset() just returns "utf-8" now.
The TranslatorDecoder not used for the translator classes.
src/translatordecoder.h removed, winbuild/Doxygen.vcproj updated

When running... doxygen/doc>py translator.py
This script should be updated. All translators do use UTF-8
internally.  The TranslatorDecoder adapter should be removed
from the code and its usage should not be checked any more.

(I do not believe I ever had so much time to add a check like this
to the translator.py :)
doc/translator.py -- TranslatorDecoder checks removed
src/translator.h simplified, translator.cpp removed,

... winbuild/Doxygen.vcproj removed.

The conversion tables/functions from within translator classes not used
after conversion to UTF-8.
idLanguageCharset() method removed from all translator classes