[case] implement compatibility caseless match

manakai-core / Whatpm / manakai-charlib / CharClass / WebHACC / Harusame / regexp

[case] implement compatibility caseless match - TODO

We need to implement "compatibility caseless match", which seems not necessarily equivalent to the comparison by Perl's |lc| function.

It is necessary to implement |map| element's |name| attribute's processing and validation.

[Good Job!]