1.4.0

[adleong]

Linkerd 1.4.0 upgrades us to the latest versions of Finagle and Netty and
features lower memory usage for large payloads. Two new configuration options
have been introduced: client connection lifetimes and access log rotation
policy. One breaking change has been introduced around the configuration file
syntax for loggers. This release features contributions from ThreeComma,
ScalaConsultants, Salesforce, and Buoyant.

• Breaking Change: Rename the loggers section of the Linkerd config to requestAuthorizers to match the name of the plugin type (#1900)
• Tune Netty/Finagle settings to reduce direct memory usage (#1889). This should dramatically reduce direct memory usage when transferring large payloads.
• Introduce a ClientSession configuration section that provides ways to control client connection lifetime (#1903).
• Expose rotation policy configuration for http and http2 access logs (#1893).
• Stop logging harmless reader discarded errors in k8s namer (#1901).
• Disable autoloading of the default tracer in Namerd (#1902). This prevents Namerd from attempting to connect to a Zipkin collector that doesn't exist.
• Upgrade to Finagle 18.4.0.

Signed-off-by: Alex Leong alex@buoyant.io