slightly better formatting of the flags in msg.String()
slightly better formatting of the flags in msg.String()

curtiszimmerman/dns,michaelharo/dns,tonnerre/golang-dns,Psiphon-Inc/dns,cloudflare/dns,bragr/dns,ezoic/dns,jmhodges/dns,FiloSottile/dns,jdef/dns,tsenart/dns,tempbottle/dns,modulexcite/dns,josephyzhou/dns,benbearchen/dns,ym/go-dns,janstk/dns,bboreham/dns,Git-Host/dns,ErikDubbelboer/dns,hugozhu/dns,letsencrypt/dns,miekg/dns,rolandshoemaker/dns,asergeyev/dns,flebarbe/dns,skynet/dns,skyportsystems/dns,AlexCheong/dns