RE: [ACTION 189] Split special requirements into several data categories

Hi Micha,

On ForbbidenChars:

- The attribute is called specialRequirementsForbiddenChars but the examples use forbiddenCharacters. The name in the list of attribute probably should be forbiddenCharacters.

- The text is several places states that this data category is to specify forbidden characters in the translation. I'm not saying it's wrong, but I wonder if its shouldn't be less specific and apply to the content in general (source and translation).

- For the value of forbiddenCharacters: Here is a first stab at a description:

A forbiddenCharacters attribute that contains a regular expression matching the characters which are not allowed. The regular expression syntax is restricted to a basic character class pattern: the enumeration of the characters between square brackets ('[', and ']'). One or more operators '-' may be used to indicate ranges. The prefix '^' may be used to invert the selection. The characters '\', '-', ']', '[' and '^' must be prefixed with '\' when used as literal. Any literal character may be expressed using the \uHHHH notation, where HHHH is the Unicode code point of the character.
Examples:
- [abc] disallows the characters 'a', 'b' and 'c'. 
- [a-c] disallows the characters 'a', 'b' and 'c'.
- [a-cA-C] disallows the characters 'a', 'b', 'c', 'A', 'B', and 'C'.
- [^abc] disallows any characters except 'a', 'b', and 'c'.
- [^a-c] disallows any characters except 'a', 'b', and 'c'.
- [\u0061-c] disallows any characters except 'a', 'b', and 'c'.
- [\-\[\]] disallows the characters '-', '[' and ']'.

Arle may be able to express this in better English.

Cheers,
-ys