@Override
    public String accentDrop(String input, Language language) {
        return pattern.matcher(Normalizer.normalize(input, Normalizer.Form.NFD)).replaceAll("");
    }
Converts all accented characters into their de-accented counterparts followed by their combining diacritics, then
strips off the diacritics using a regex.

@author Simon Thoresen Hult
linguistics/src/main/java/com/yahoo/language/simple/SimpleTransformer.java