CHANGES (p.happy-eyeballs.1.2.2.doc.CHANGES)

Allow timeouts and delays in connect, connect_ip, connect_host to overwrite the default from create (#42 @hannesm)

Reverse dependency between dns-client-lwt and happy-eyeballs-lwt, dns-client-mirage and happy-eyeballs-mirage (#38 @dinosaure) This now has a new function inject to put a name resolver getaddrinfo into action. The default for happy-eyeballs-lwt is Lwt_unix.getaddrinfo. For happy-eyeballs-mirage, there is no default.
Update timestamp when a fresh connection attempt is done (#37 @hannesm)
Log message: prepend with counter to distinguish multiple happy-eyeballs instaces (#36 @hannesm)

Fix connection establishment: parallelize connection attempts, deal with servers dropping packets (such as the Azure DNS resolver)
Introduce connect_delay (when to start the next connection attempt)
Deal with connect_timeout properly
Revise log output (IP vs domain name, fewer logs on debug level)

All in #34, @hannesm, reviewed by @reynir -- sponsored by Semgrep Inc

Cancellation of connection attempts (#30 @reynir @hannesm, fixes #27)
Make the type id abstract (suggested by @reynir in #30)
Add reason for failures to the variants, improves log output (#30, fixes #7, @hannesm @reynir)
Remove log messages about DNS resolution success/failure when there is no awaiting connection (#30, @hannesm)
Use the domain name of the fist IP address in connect_ip as identifier (this provides more useful information than the hardcoded "host.invalid") (#29, @hannesm)

Improve documentation for Happy_eyeballs.timer (#24, #25 @reynir, review by @hannesm and @bikallem)
Demote log levels that are (likely) caused by missing cancellation (#26 @reynir)

Happy_eyeballs_mirage.connect_device: remove int64 argument (timestamp), use monotonic clocks C.elapsed_ns () instead (noticed by @dinosaure)

Happy_eyeballs_mirage: add a module type signature to allow creation of a MirageOS device (#22 @dinosaure)
happy-eyeballs-lwt: update to cmdliner 1.1.0 (@hannesm)

Happy_eyeballs.create: add v6_connect_timeout parameter - the amount of nanoseconds (default: 200ms) after which to attempt IPv4 connection establishment. (#21 @hannesm, review by @reynir, issue reported at robur-coop/http-lwt-client#8 by @kit-ty-kate)
Happy_eyeballs.create: add resolve_retries - the amount of resolve attempts when a (resolve) timeout occurs (default: 3). (#21 @hannesm, review by @reynir, issue reported at robur-coop/http-lwt-client#8 by @kit-ty-kate)

Happy_eyeballs_{lwt,mirage}: update to tcpip 7.0.0, remove mirage-stack dependency (#20 @dinosaure)

Happy_eyeballs_lwt.create and Happy_eyeballs_mirage.create now take an optional ?happy_eyeballs:Happy_eyeballs.t argument, and also an optional ?dns:Dns_client_lwt.t/DNS.t argument. This avoids the need to forward all potential creation arguments of Happy_eyeballs and DNS. (#19 @hannesm)
Fix state machine: if Connecting fails, and resolved is not yet both, return to Resolving (instead of Error) (#13 @hannesm, similar to d0d4ef5ea2aaf2de407ba84742c5648489c47e1f #9)
Add a state machine diagram (happy_eyeballs.dot) (#13 @hannesm)

Remove assertion in timer, and fix the code (reported by @dinosaure in #17, fix in #18 by @hannesm, reviewed by @reynir)
Support OCaml 4.08 (#18 hannesm, requested in #16 by @smorimoto)

return a variant from timer to indicate whether there are connections pending or the timer can be suspended -- this avoids unnecessary busy work (@reynir)
connect_ip: take list of Ipaddr.t and int pairs instead of separate lists. The reason for this change is the dns-client. (@hannesm @reynir)

connect_ip: take an optional shuffle argument and an ordered list of ips to attempt connections to. The reason for this change is that /etc/resolv.conf specifies an ordering. (@hannesm)

BUGFIX: Delay connect failure if v6 resolution and connection attempt fails before v4 resolution had a chance to succeed or fail (issue #9). (@hannesm)