bug#36717: 25.3; greek.el: deprecated vowel+oxia combinations should be replaced with vowel+tonos counterparts

[Robert Pluim <rpluim@gmail.com>]

>>>>> On Fri, 19 Jul 2019 15:54:27 +0300, Eli Zaretskii <eliz@gnu.org> said:

    >> From: Robert Pluim <rpluim@gmail.com>
    >> Cc: Eli Zaretskii <eliz@gnu.org>,  36717@debbugs.gnu.org
    >> Date: Fri, 19 Jul 2019 11:49:47 +0200
    >> 
    >> <https://www.unicode.org/faq/greek.html> says:
    >> 
    >> Q: Which block of Greek characters should I use?
    >> 
    >> A: The answer to that is that it depends what you are doing. But
    >> generally, the basic Greek block plus the use of the generic combining
    >> marks in the Combining Diacritical Marks block (U+0300..U+036F) is the
    >> best approach to polytonic Greek support.

    Eli> To me, the most important part of this is in the very first sentence.
    Eli> It is not our business to second-guess "what the user is doing".  We
    Eli> should just make sure they can produce both variants of the characters
    Eli> involved, and let the user decide what they want/need.

That pleads for us doing nothing, since we have that today (just not
within the same input method).

Robert