Convert NQPRegex.ACCEPTS to be multimethods based on concrete-ness.
Convert NQPRegex.ACCEPTS to be multimethods based on concrete-ness.

cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp