consider "modifier letter apostrophe" to be punctuation

consider "modifier letter apostrophe" to be punctuation

While technically being a letter, the apostrophe is often replaced
with a normal apostrophe in writing which is a punctuation mark.
This makes sure that the modifier letter apostrophe yields the same
normalization results and thus is really interchangable.

Only has an effect after the next reimport.

Fixes #2569.