Closes: #873125

This is one of the few/only places where both 'source package control
file' and 'Debian source control file' are used.

source control files == .dsc

Thanks to Mattia Rizzolo for catching this error.

This is an informative change, so I am committing immediately.

- dpkg adds to binary control files
- dpkg uses value 'autopkgtest'
- 'autopkgtest' is not the only defined value

* Add a footnote documenting a (complex) command that returns the Debian
  package name for a shared library.  Thanks, Jakub Wilk and Julien
  Cristau.  (Closes: #661928)

After some more experimentation, I can convince Emacs to indent
footnote text a little better, which I think makes this more
readable.

* Reformat the shared libraries chapter (8) to move footnotes to the end
  of the section of their references and use more succinct
  reStructuredText syntax.  Fix some errors in the shlibs syntax and
  examples introduced by the conversion, and missing newlines in the
  footnote illustrating alternative templates that were lost in the
  DocBook translation.

Also rename the autosave file so that wildcards match.

* Rename the info document to debian-policy.info to make it less
  generic, and update the PNG file names accordingly.  (Closes: #872900)

* Restructure the document to ensure proper section numbering in info
  and PDF output except for the appendices.  The appendix numbering
  will require a Sphinx change.  (Closes: #872893)

dh_sphinxdoc cannot correctly process single-file HTML, so manually
do this for the Javascript used by the single-file HTML file.

* Revert the contents of the policy.html directory to the multi-page
  HTML output.  (Closes: #872895)
* Move the single-page HTML output to policy-1.html, matching the
  previous file name, and add the supporting _images and _static
  directories to /usr/share/doc/debian-policy.
* Remove the stray policy.html.tar.gz file from the built package.
* Simplify the build rules for generating policy.html.
* Remove some stray build rules left over from DocBook Policy.

* Add back missing parentheses around the man page section in man page
  references in the Policy manual, lost in the conversion to
  reStructuredText.  Thanks, Daniel Shahaf.

"Significant changes that will require work in many packages will be
signaled by a change to the minor number."

5% of the archive is not yet reproducible, and this seems to count as
"many packages".

- rename so as to namespace our files
- install into /usr/share/info so info readers can display them