8.0.0

CHANGES:

• dns-client (lwt, mirage): depend on happy-eyeballs-{lwt,mirage} instead of
  duplicating the code. This requires happy-eyeballs 1.1.0, and now the same
  Happy_eyeballs_{lwt,mirage}.t is used for DNS (connecting to the nameserver)
  and for the application (connecting to a remote host)
  (@dinosaure @hannesm #346)
• server: improve API documentation (@hannesm
  1a80bd4
  000ae02)
• server: add a packet_callback to handle_packet and handle_buf
  (@RyanGibb #349)
• server: expose update_data (@RyanGibb #350)
• resolver: b root name server IP change (@hannesm #348)
• secondary server [mirage]: avoid infinite loop in connect (avoids SYN floods)
  (@hannesm @reynir #347)
• resolver, dns_zone: use consistently Log instead of Logs (@palainp #342)