Update release notes

Signed-off-by: Sahas Subramanian <sahas.subramanian@proton.me>

Author: shsms

RELEASE_NOTES.md

@@ -2,19 +2,22 @@
 
 ## Summary
 
-<!-- Here goes a general summary of what this release is about -->
+The main change in this release is the introduction of the `OneshotChannel` and `BroadcastChannel` classes, and the deprecation of the `Broadcast` and `Anycast` classes.
 
 ## Upgrading
 
 - `LatestValueCache` now closes the receiver when it is stopped.
+
 - Fetching values from stopped `LatestValueCache` instances is now disallowed.
 
+- The old `Broadcast` class is deprecated in favour of the new auto-closing `BroadcastChannel`.
+
+- The `Anycast` class is deprecated, because of the lack of use-cases and the maintenance cost.
+
 ## New Features
 
-- There's a new `Oneshot` channel, which returns a sender and a receiver.  A single message can be sent using the sender, after which it will be closed.  And the receiver will close as soon as the message is received.
+- There's a new `OneshotChannel`, which returns a sender and a receiver.  A single message can be sent using the sender, after which it will be closed.  And the receiver will close as soon as the message is received.
 
 - `Sender`s now have an `aclose`, which must be called, when they are no-longer needed.
 
-## Bug Fixes
-
-<!-- Here goes notable bug fixes that are worth a special mention or explanation -->
+- There's a new `BroadcastChannel`, which returns a broadcast sender and a broadcast receiver.  The channel is auto-closing, meaning when all the senders or all the receivers are closed, the channel is closed.