CHANGELOG and docstring

CHANGELOG.md

@@ -5,6 +5,14 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [5.0.0-rc1]
+
+[5.0.0-rc1]: https://github.com/microsoft/CCF/releases/tag/ccf-5.0.0-rc1
+
+### Added
+
+- The `cchost` configuration file now includes an `idle_connection_timeout` option. This controls how long the node will keep idle connections (for user TLS sessions) before automatically closing them. This may be set to `null` to restore the previous behaviour, where idle connections are never closed.
+
 ## [5.0.0-rc0]
 
 [5.0.0-rc0]: https://github.com/microsoft/CCF/releases/tag/ccf-5.0.0-rc0

doc/host_config_schema/cchost_config.json

@@ -665,7 +665,7 @@
     "idle_connection_timeout": {
       "type": ["string", "null"],
       "default": null,
-      "description": "Timeout for idle connections. Null enforces no timeout."
+      "description": "Timeout for idle connections. Null is a valid option, and means idle connections are retained indefinitely"
     },
     "worker_threads": {
       "type": "integer",