[Haskell-cafe] heads-up: tls v2.0.0

[Kazu Yamamoto (=?iso-2022-jp?B?GyRCOzNLXE9CSScbKEI=?=)]

Hello guys,

I'm planning to release the "tls" package v2.0.0 probably within one
month. It removes TLS 1.0/1.1 and provides only TLS 1.2/1.3 with safe
cipher suites according to recent RFCs and internet-drafts.

This version does not change the default usage. But if you are using
custom parameters, you might have to modify your code.  This breaking
change is *intentional* to notice users that they are using vulnerable
versions and/or parameters.

The attached is the current change log.

--Kazu

## Version 2.0.0
* `tls` now only supports TLS 1.2 and TLS 1.3 with safe cipher suites.
* Security: BREAKING CHANGE: TLS 1.0 and TLS 1.1 are removed.
* Security: BREAKING CHANGE: all CBC cipher suite are removed.
* Security: BREAKING CHANGE: RC4 and 3DES are removed.
* Security: BREAKING CHANGE: DSS(digital signature standard) is removed.
* Security: BREAKING CHANGE: TLS 1.2 servers require
  EMS(extended master secret) by default.
* BREAKING CHANGE: the package is now complied with `Strict` and `StrictData`.
* BREAKING CHANGE: Many data structures are re-defined with
 `PatternSynonyms` for extensibility.
* BREAKING CHANGE: the structure of `SessionManager` is changed
  to support session tickets.
* API: `handshake` can receive an alert of client authentication failure
  for TLS 1.3
  [#463](https://github.com/haskell-tls/hs-tls/pull/463)
* API: `bye` can receive NewSessionTicket for TLS 1.3
* Channel binding: `getFinished` and `getPeerFinished` are deprecated.
  Use `getTLSUnique` instead.
* Channel binding: `getTLSExporter` and `getTLSServerEndPoint` are provided.
  [#462](https://github.com/haskell-tls/hs-tls/pull/462)
* Refactoring: the monolithic `handshake` is divided to follow
  the diagram of TLS 1.2 and 1.3 for readability.
* Refactoring: test cases are refactored for maintenability
  and readablity. `hspec` is used instead of `tasty`.
* Code format: `fourmolu` is used as an official formatter.