peg.ebnf-docs: add note on including "-" in the character classes
peg.ebnf-docs: add note on including "-" in the character classes

factor/factor,tgunr/factor,mrjbq7/factor,bpollack/factor,bpollack/factor,AlexIljin/factor,bpollack/factor,mrjbq7/factor,tgunr/factor,factor/factor,AlexIljin/factor,tgunr/factor,AlexIljin/factor,factor/factor,mrjbq7/factor,AlexIljin/factor,bpollack/factor,bpollack/factor,AlexIljin/factor,factor/factor,factor/factor,AlexIljin/factor,tgunr/factor,bpollack/factor,tgunr/factor,mrjbq7/factor,mrjbq7/factor,AlexIljin/factor,factor/factor,mrjbq7/factor,tgunr/factor,bpollack/factor