https://stackoverflow.com/questions/6579844/how-does-zalgo-text-work
http://archives.miloush.net/michkap/archive/2006/02/17/533929.html
https://stackoverflow.com/questions/32921751/how-to-prevent-zalgo-text-using-php
https://stackoverflow.com/questions/11978912/how-to-protect-against-diacritics-such-as-zalgo-text?rq=1
zalago, diacritics