The most important parts of almost any release notes are the
language and tool changes. Those should be the first two sections.
Instead Ports interrupts the flow with information that usually
matters only to very few users.
Move Ports to the end of the release notes.
Change-Id: I78492e91e368184fb5f8e8d44d63f35b8f14eeae
Reviewed-on: https://go-review.googlesource.com/c/go/+/500957
TryBot-Bypass: Russ Cox <rsc@golang.org> Reviewed-by: Ian Lance Taylor <iant@google.com>