=str #15355: fix race with ExposedPublisher messaage in tee

 - this change makes the secondary subscription lazy
Merge pull request #15367 from drewhk/wip-15355-tee-first-message-race-drewhk

=str #15355 Fix race in Tee causing a RequestMore overtaking ExposedPublisher
!str Extend StreamIO API with `idleTimeout` config setting, improve `connectTimeout` model (refs #15401)
!hco Add client-side request rendering and response parsing, refactor, strip-down

Remove everything that is out of scope for akka-http-core M1.
Things like the host- and request-level client-side API will be added back later.
=hco Remove `Low-Level API Design.rst`
+hco Java model for http-core
=hco Changes needed to compile with java 6 on mac
Merge pull request #15403 from spray/release-2.3-dev-http

akka-http-core: remaining functionality for M1
Merge pull request #15398 from spray/http-model-java-latest

Latest version of Java HTTP model
=doc first parts of HTTP model documentation