message: [docs] Update release-notes.md
  Write an introduction explaining how to use the release-notes.md template.
  Adapt and merge the updates in
diff: -(note: this is a temporary file, to be added-to by anybody, and moved to
  -release-notes at release time)
  +*After branching off for a major version release of Bitcoin Core, use this
  +template to create the initial release notes draft.*
  +
  +*The release notes draft is a temporary file that can be added to by anyone. See
  +[/doc/developer-notes.md#release-notes](/doc/developer-notes.md#release-notes)
  +for the process.*
  +
  +*Create the draft, named* "*version* Release Notes Draft"
  +*(e.g. "0.20.0 Release Notes Draft"), as a collaborative wiki in:*
  +
  +https://github.com/bitcoin-core/bitcoin-devwiki/wiki/
  +
  +*Before the final release, move the notes back to this git repository.*
  +
  +*version* Release Notes Draft
  +===============================
  Bitcoin Core version *version* is now available from:
  