When converting some text to Small Caps or All Caps (via the corresponding
character formatting commands), Greek accented letters should be converted to
the respective non-accented uppercase letters. The required conversions are the
following (in Unicode):
ά -> Α
έ -> Ε
ή -> Η
ί -> Ι
Π-> Ϊ
ό -> Ο
Ï -> Î¥
ΰ -> Ϋ
ώ -> Ω

Also diphthongs (two-vowel constructs) should be converted as follows, when the
first vowel is accented:
άι -> ΑΪ
έι -> ΕΪ
όι -> ΟΪ
Ïι -> ΥΪ
άυ -> ΑΫ
έυ -> ΕΫ
ήυ -> ΗΫ
όυ -> ΟΫ

In the current implementation, this is not the case: Greek accented lowercase
letters are merely converted to the respective (accented) uppercase letters.

I should note that when converting some text to "Titling" (first letter of each
word capitalized) then the above does not hold, i.e. accented letters should be
converted to accented uppercase.