Wrong reversed transliteration for some Greek capital letters

[GianniGT]

The reversed_specific_mapping tuple for Greek contains only lower case letters:

reversed_specific_mapping = (
u"ςάέήίύόώϊϋΐΰωΩηΗϵϱ",
u"saeiiyooiyiyooiier"
)

the reverse transliteration of capital Greek letters doesn't work. For instance the capital letter Ϊ is not transliterated.

A possible fix is to programmatically add the capital version of each symbol in base.py with something like this:
(...)

        _for key, val in zip(self.reversed_specific_mapping[0].**upper()**, self.reversed_specific_mapping[1].**upper()**):
            self.reversed_specific_translation_table.update(
                {ord(key): ord(val)}
            )_

[barseghyanartur]

@GianniGT

Thanks for bringing this up.

There have been numerous attempts and PRs to bring corectness to Greek transliteration.

I'm all open for correctness and thus willing to accept a valid PR.

I think back in the day, I have used this Wikipedia article as a valid and trustworthy source of information on the topic.

Could you please double check your findings with the mentioned Wikipedia article and let me know if current interpretation of transliterate isn't correct?

Thank you!