Convert numbers to number words in a number of languages. Each language has
its own module. The module name is based on the ISO 639-3 code for that
language. Each module contains one or more cardinal and ordinal functions
and a struct function. The cardinal functions directly convert cardinal
numbers to a string-like representation of their spoken form. The ordinal
functions do the same but for ordinal numbers. The struct functions convert
numbers to a polymorphic representation of their grammatical structure.
See the Text.Numeral module for information on how to use this library.