Some more fixes to built-in rules
Some more fixes to built-in rules

* add a few Unicode property alternatives
* delete <word> and <ascii>, which do not exist
* add <wb> and <ww>

See #973

tbrowder/doc,gfldex/doc,MasterDuke17/doc,MasterDuke17/doc,antquinonez/doc,perl6/doc,tbrowder/doc,antquinonez/doc,dmaestro/doc,perl6/doc,stmuk/doc,antquinonez/doc,jonathanstowe/doc,stmuk/doc,gfldex/doc,stmuk/doc,dmaestro/doc,antquinonez/doc,jonathanstowe/doc,jonathanstowe/doc,perl6/doc,tbrowder/doc,stmuk/doc,stmuk/doc,antquinonez/doc,jonathanstowe/doc,dmaestro/doc,perl6/doc,perl6/doc,MasterDuke17/doc,gfldex/doc,dmaestro/doc,jonathanstowe/doc,gfldex/doc,tbrowder/doc,gfldex/doc,MasterDuke17/doc,dmaestro/doc