Ruby Bindings for the GNU LibIDN library, an implementation of the
Stringprep, Punycode and IDNA specifications defined by the IETF
Internationalized Domain Names (IDN) working group.

Included are the most important parts of the Stringprep, Punycode and
IDNA APIs like performing Stringprep processings, encoding to and
decoding from Punycode strings and converting entire domain names to and
from the ACE encoded form.