Add ReplaceCallback
Add ReplaceCallback

SeanThomasWilliams/go-ircevent,DanielOaks/girc-go,alaska/go-ircevent,Elemental-IRCd/irc,HenrySlawniak/go-ircevent,iwanbk/ogric,phone/go-ircevent,dainis/go-ircevent,pratikmallya/go-ircevent,oniichaNj/go-ircevent