docs: add more Rustls detail to 2.10.0 CHANGELOG

* Try to group Rustls related items (but leaving the MSRV note
  up-front).
* Put the doc update RE: IP addresses last, it's perhaps least
  interesting to folks evaluating an update.
* Explicitly call out that the Rustls update from 0.22 to 0.23 occurred,
  and is a breaking change for consumers that were using their own
  Rustls 0.22 dep to construct configs given to ureq. The Rustls 0.23
  changelog is linked to discuss the upstream changes in detail.
* Expand on the implications of ureq activating the `ring` feature by
  default. In particular you must either ensure Rustls features are
  unambiguous or install a process-wide default provider before building
  configs, or having ureq build you a config.

CHANGELOG.md

@@ -4,10 +4,22 @@
   * Bump MSRV 1.61 -> 1.63 due to rustls (#764)
   * Update deps (only patch versions in Cargo.lock) (#763)
   * Refork frewsxcv/rust-chunked-transfer to fix MIT/Apache2.0 license (#761)
-  * Fix doc Rustls does now support IP address certificates (#759)
   * Enable http-crate feature for docs (#755)
-  * Rustls dep to default to ring backend (#753)
+  * Update Rustls from 0.22 to 0.23 - this may be a breaking change if your
+    application depends on Rustls 0.22 (e.g. to provide a custom 
+    `rustls::ClientConfig` to `ureq`). See the [Rustls 0.23.0][rustls-0.23.0]
+    changelog for a list of breaking API changes (#753)
+  * Rustls dep to default to ring backend. If your project uses the
+    default `ureq` TLS config, or constructs its own `rustls::ClientConfig`
+    with `rustls::ClientConfig::builder()` you must ensure the Rustls 
+    `aws-lc-rs` feature is not activated, or set the process default 
+    cryptography provider before constructing any configs. See the Rustls
+    [CryptoProvider][CryptoProvider] docs for more information (#753)
   * Remove direct dep rustls-webpki (#752)
+  * Fix doc Rustls does now support IP address certificates (#759)(#753)
+
+[rustls-0.23.0]: https://github.com/rustls/rustls/releases/tag/v%2F0.23.0
+[CryptoProvider]: https://docs.rs/rustls/latest/rustls/crypto/struct.CryptoProvider.html#using-the-per-process-default-cryptoprovider
 
 # 2.9.7