NEWS template breaking chm generation

[Ian Clatworthy]

This sections at the end of NEWS is breaking doc generation when executed on Windows ...

  bzr ?.?.? (not released yet)
  ############################

  :Codename: template
  :2.0.2: ???

  ...

It's not a problem generally because we generate the HTML and PDFs on GNU/Liinux. It does break CHM generation on Windows though.

One potential fix is to just ignore this section while splitting NEWS into the various doc/en/release-notes topics.

[Martin Pool (mbp)]

Actually I think it looks a bit crap to have this visible to Unix
users too. Let's move it to a separate file.

[Andrew Bennetts (spiv)]

Ideally the template wouldn't be part of the final output for human consumption. I don't have an opinion on whether we filter it out when splitting into doc/en/release-notes/* or put it in a separate file, or something else.

On a vaguely related note, the news_merge plugin would like to use this template to help inform its merges (so that it can enforce a standard ordering of sections).