Updating server dependancies. Also adding github.com/jaytaylor/html2text and gopkg.in/gomail.v2 (#5748)

vendor/github.com/miekg/dns/README.md

@@ -25,6 +25,7 @@ two versions of Go, currently: 1.6 and 1.7.
 
 A not-so-up-to-date-list-that-may-be-actually-current:
 
+* https://github.com/coredns/coredns
 * https://cloudflare.com
 * https://github.com/abh/geodns
 * http://www.statdns.com/
@@ -54,6 +55,8 @@ A not-so-up-to-date-list-that-may-be-actually-current:
 * https://github.com/mehrdadrad/mylg
 * https://github.com/bamarni/dockness
 * https://github.com/fffaraz/microdns
+* http://quilt.io
+* https://github.com/ipdcode/hades (JD.COM)
 
 Send pull request if you want to be listed here.
 
@@ -142,6 +145,7 @@ Example programs can be found in the `github.com/miekg/exdns` repository.
 * 6975 - Algorithm Understanding in DNSSEC
 * 7043 - EUI48/EUI64 records
 * 7314 - DNS (EDNS) EXPIRE Option
+* 7828 - edns-tcp-keepalive EDNS0 Option
 * 7553 - URI record
 * 7858 - DNS over TLS: Initiation and Performance Considerations (draft)
 * 7873 - Domain Name System (DNS) Cookies (draft-ietf-dnsop-cookies)