Log Message:
Import libkkc-0.3.3 as converters/libkkc.

libkkc provides a converter from Kana-string to
Kana-Kanji-mixed-string.  It was named after kkc.el in GNU Emacs, a
simple Kana Kanji converter, while libkkc tries to convert sentences
in a bit more complex way using N-gram language models.