Update release notes

doc/qbk/release_notes.qbk

@@ -11,6 +11,92 @@
 
 [/-----------------------------------------------------------------------------]
 
+[heading Boost 1.74]
+
+[*API Changes]
+
+* The API to Asio has undergone changes. Please refer to the Asio release notes for details.
+
+* Beast has been updated to track and respect developer choices in the use of Asio. In particular:
+ * Define `BOOST_ASIO_NO_DEPRECATED` to disallow deprecated invocation and allocation hooks.
+ * Define `BOOST_ASIO_NO_TS_EXECUTORS` to ensure that executors conform to the
+   [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p0443r11.html Standard Executors] proposal.
+ * Define `BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT` to select
+   [@https://cplusplus.github.io/networking-ts/draft.pdf Networking TS] style executors by default.
+   If this macro is not defined, Asio default executors will be the
+   [@http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p0443r11.html Standard Executors] implementation.
+
+* [issue 1897] Parser `body_limit` is optional (API Change)
+  ['Actions Required]
+  * The signature of `basic_parser<>::body_limit(n)` has changed. It now accepts an
+    optional `std::uint64_t`. The caller may indicate that no body limit is required
+    by calling `body_limit(boost::none)``. The default limits remain in place in order
+    to maintain 'safe by default' behaviour.
+
+* [issue 1934] Remove deprecated interfaces (API Change)
+  ['Actions Required]
+  * The macro `BOOST_BEAST_NO_DEPRECATED` will no longer be noticed by Beast. The only way to
+    enable deprecated functionality is now the macro `BOOST_BEAST_ALLOW_DEPRECATED` which is
+    undefined by default. That is, all deprecated behaviour is disabled by default.
+  * The following deprecated functions have been removed:
+    - `websocket::async_accept_ex`
+    - `websocket::async_handshake_ex`
+    - `websocket::accept_ex`
+    - `websocket::handshake_ex`
+    Programs still using these names should be refactored to use the `decorator` feature and
+    the remaining handshake and accept functions.
+  * `websocket::role_type` has been removed. Users should use `beast::role_type` instead.
+  * `handler_ptr` has been removed. Users should use `net::bind_handler` and/or
+    `bind_front_handler` instead.
+  * Code that depends on `mutable_data_type` should be refactored to use
+    `mutable_buffers_type`. Classes affected are:
+    - `buffers_adaptor`
+    - `flat_buffer`
+    - `flat_static_buffer`
+    - `multi_buffer`
+    - `static_buffer`
+  * The `reset` function has been removed from `flat_static_buffer`. Use the
+    `clear` function instead.
+  * The `core/type_traits.hpp` public header has been removed and along with it
+    the type trait `is_completion_handler`. Beast uses the CompletionHandler correctness
+    checks provided by Asio. In a c++20 environment, these convert to concept checks.
+  * The error code enum `invalid_code_lenths` (sic) was a synonym of `invalid_code_lengths`.
+    Affected programs should be modified to use `invalid_code_lengths`.
+  * The file `core/buffers_adapter.hpp` has been removed along with the deprecated
+    alias typename `buffers_adapter`. Affected programs should use
+  `  core/buffers_adapator.hpp` and the type `buffers_adaptor`.
+
+* [issue 1956] Deprecate `string_param` (API Change)
+  ['Actions Required]
+  `string_param`, which was previously the argument type when setting field values
+  has been replaced by `string_view`. Because of this, it is no longer possible to
+  set message field values directly as integrals.
+  Users are requied to convert numeric arguments to a string type prior to calling
+  `fields::set` et. al.
+  Beast provides the non-allocating `to_static_string()` function for this purpose.
+  To set Content-Length field manually, call `message::content_length`.
+
+[*Fixes]
+
+* [issue 1913] Fix standalone compilation error with `std::string_view`
+* [issue 1925] [issue 1916] Fix compile errors on Visual Studio with /std:c++latest
+* [issue 1924] Fix c++20 deprecation warning in `span_body`
+* [issue 1920] Fix use `buffered_read_stream` with `use_awaitable`
+* [issue 1918] Fix `async_detect_ssl` with `use_awaitable`
+* [issue 1944] Fix `FILE` namespace qualification
+* [issue 1942] Fix http read `bytes_transferred`
+* [issue 1943] Fix `basic_stream` `expires_after`
+* [issue 1980] Fix `max` compile error
+* [issue 1949] `iless` and `iequal` take part in Heterogeneous Lookup
+
+[*Miscellaneous]
+
+* [issue 1907]  OpenSSL 1.0.2 or later is required when using SSL/TLS streams.
+  This is a requirement inherited from Boost.Asio.
+
+* Additional tests have been added to ensure correct integration with C++20
+  coroutines when avaialable.
+
 [heading Boost 1.73]
 
 [*API Changes]