Unicode canonicalization in examples and map entries

[antonsviridenko]

Unicode characters can be represented in multiple ways, for example "č" can be
010D LATIN SMALL LETTER C WITH CARON
or
0063 LATIN SMALL LETTER C
030C COMBINING CARON
#231 (comment)

Therefore it is important to perform Unicode canonicalization on all inputs: character map entries, testing examples and input texts to be converted.

[ronaldtse]

I found this article to be a good introduction of using Ruby for Unicode normalization: https://www.honeybadger.io/blog/ruby-unicode-normalization/