[csa] use better Unicode characters

[moyogo]

• replace e̷ <0065,0337> by ɇ <0247>

[moyogo]

I think the following character substitutions should be made:

• †̱̎ <2020,0331,030D> by ɨ̱ <0268,0331>, occuring 2 times
• †̱̎ <2020,0331,030E> by ɨ̱̈ <0268,0331,0308>, occuring 1 time
• †̍ <2020,030D> by ɨ <0268>, occuring 46 times
• †̎ <2020,030E> by ɨ̈ <0268,0308>, occuring 137 times
• † <2020> by ɨ <0268>, occuring 24 times Note that <2020,0331> doesn’t occured without being followed by either 030D or 030E, but 2020 does occur without either.

I haven’t found a useful Chiltepec Chinantec reference yet, but some other Chinantec languages use the letter ɨ, the macron below to indicate low tone, the acute for high tone and neither for medium tone. These diacritics are also used in this Chiltepec Chinantec translation.

I’m not sure 030D should be read as a tittle on ɨ or as an acute since some occurences of 2020 aren’t followed by any combining mark. It definitely shouldn’t be an acute when the macron below is used as only one tone mark can be used.