Progress: UTF-8

Progress: UTF-8

More UTF-8 improvements.

The Punctuation is complete as far as the "Other" punctuation category is concerned.
(Apparently, there are more groups/sets to do!)

Create a new whitespace functions (is_whitespace_other()) to handle non-whitespace whitespace.
So far, this is only a single character: Ogham space mark ( ).
This Ogham space mark is not a whitespace, it is a graph character that is considered a whitespace.

Add some @todos.

Remove invalid whitespace character().

Add is_digit() vs is_numeric().
The traditional alnum() is referring to alphabet and digit.
With UTF-8 there are non-digit numbers, which can be classified as "numeric".
Therefore, the is_digit() functions are added and intended to be used for the traditional behavior.
The is_numeric() are intended to handle any numeric character.
The is_word() tests are for digits and not for numeric.