Prepare 0.2.23 release

[Darksonn]

0.2.23 (November 11, 2020)

Fixes

• time: report correct error for timers that exceed max duration (time: report correct error for timers that exceed max duration #2023)
• time: fix resetting expired timers causing panics (Address issue 2473 #2587)
• macros: silence unreachable_code warning in select! (Fix select macro giving warning when branch's returns never #2678)
• rt: fix potential leak during runtime shutdown (Fix #2641, #2535, and shutdown_timeout blocking for no reason #2649)
• sync: fix missing notification during mpsc close (sync: fix missing notification during mpsc close #2854)

Changes

• io: always re-export std::io (io: always reexport std::io types needed to implement async io traits #2606)
• dependencies: update parking_lot dependency to 0.11.0 (Update optional parking_lot dependency to 0.11.0 #2676)
• io: rewrite read_to_end and read_to_string (io: rewrite read_to_end and read_to_string #2560)
• coop: reset coop budget when blocking in block_on (Reset coop budget when blocking in block_on #2711)
• sync: better Debug for Mutex (Better Debug for Mutex #2725)
• net: make UnixListener::poll_accept public (Change UnixListener::poll_accept to public #2880)
• dep: raise lazy_static to 1.4.0 (ci: minimal version check (v0.2.x) #3132)
• dep: raise slab to 0.4.2 (ci: minimal version check (v0.2.x) #3132)

Added

• io: add io::duplex() as bidirectional reader/writer (tokio: introduce io::Duplex #2661)
• net: introduce split and into_split on UnixDatagram (net: introduce split on UnixDatagram #2557)
• net: ensure that unix sockets have both split and into_split (Ensure that unix sockets have both split and into_split #2687)
• net: add try_recv/from & try_send/to to UnixDatagram (Added try_recv & try_send to UnixDatagram #1677)
• net: Add UdpSocket::{try_send,try_send_to} methods (net: Add UdpSocket::{try_send,try_send_to} methods #1979)
• net: implement ToSocketAddrs for (String, u16) (impl ToSocketAddrs for (String, u16) #2724)
• io: add ReaderStream (Add ReaderStream #2714)
• sync: implement map methods (sync: Implement map methods of parking_lot fame #2771)

Closes: #3111

[Darksonn]

Do we need a tokio-macros release too?

error: the async keyword is missing from the function declaration
 --> tokio/tests/macros_test.rs:4:7
  |
4 | async fn test_macro_can_be_used_via_use() {
  |       ^^

error: the async keyword is missing from the function declaration
  --> tokio/tests/macros_test.rs:13:7
   |
13 | async fn test_macro_is_resilient_to_shadowing() {
   |       ^^

[carllerche]

Might need one? were there changes?

[carllerche]

It looks highly likely we need to push out a macros release first.

[Darksonn]

tokio-macros release in #3127

[Darksonn]

We should include #3132 in this.