docs: Remove the 'develop' guide

This contained a list of extensions, along with general contributing
information and pointers on how to develop your own extensions. The list
of extensions was very old, referenced the dead BitBucket repo and was
really not very helpful, while the contributing and development
information was just pointers to other, better documentation. Remove the
document wholesale and update any pointers we have to it to other,
better docs.

Signed-off-by: Stephen Finucane <stephen@that.guru>

doc/_templates/index.html

@@ -33,9 +33,9 @@
     <li>{%trans path=pathto('ext/builtins')%}<b>Extensions:</b> automatic testing of code snippets, inclusion of
       docstrings from Python modules (API docs), and
       <a href="{{ path }}#builtin-sphinx-extensions">more</a>{%endtrans%}</li>
-    <li>{%trans path=pathto('develop')%}<b>Contributed extensions:</b> more than
-      50 extensions <a href="{{ path }}#extensions">contributed by users</a>
-      in a second repository; most of them installable from PyPI{%endtrans%}</li>
+    <li>{%trans path=pathto("usage/extensions")%}<b>Contributed extensions:</b> dozens of
+      extensions <a href="{{ path }}#third-party-extensions">contributed by users</a>;
+      most of them installable from PyPI{%endtrans%}</li>
   </ul>
   <p>{%trans%}
     Sphinx uses <a href="http://docutils.sourceforge.net/rst.html">reStructuredText</a>

doc/_themes/sphinx13/layout.html

@@ -67,7 +67,7 @@
     <li><a href="{{ pathto('index') }}">Home</a></li>
     <li><a href="{{ pathto('usage/installation') }}">Get it</a></li>
     <li><a href="{{ pathto('contents') }}">Docs</a></li>
-    <li><a href="{{ pathto('develop') }}">Extend/Develop</a></li>
+    <li><a href="{{ pathto('development') }}">Extend</a></li>
   </ul>
   <div>
     <a href="{{ pathto('index') }}">

doc/develop.rst

@@ -1,153 +0,0 @@
-:orphan:
-
-Sphinx development
-==================
-
-Sphinx is a maintained by a group of volunteers.  We value every contribution!
-
-* The code can be found in a Git repository, at
-  https://github.com/sphinx-doc/sphinx/.
-* Issues and feature requests should be raised in the `tracker
-  <https://github.com/sphinx-doc/sphinx/issues>`_.
-* The mailing list for development is at `Google Groups
-  <https://groups.google.com/forum/#!forum/sphinx-dev>`_.
-* There is also the #sphinx-doc IRC channel on `freenode
-  <https://freenode.net/>`_.
-
-For more about our development process and methods, refer to
-:doc:`/internals/index`.
-
-Extensions
-==========
-
-To learn how to write your own extension, see :ref:`dev-extensions`.
-
-The `sphinx-contrib <https://bitbucket.org/birkenfeld/sphinx-contrib/>`_
-repository contains many contributed extensions.  Some of them have their own
-releases on PyPI, others you can install from a checkout.
-
-This is the current list of contributed extensions in that repository:
-
-- aafig: render embedded ASCII art as nice images using aafigure_
-- actdiag: embed activity diagrams by using actdiag_
-- adadomain: an extension for Ada support (Sphinx 1.0 needed)
-- ansi: parse ANSI color sequences inside documents
-- argdoc: automatically generate documentation for command-line arguments,
-  descriptions and help text
-- astah: embed diagram by using astah
-- autoanysrc: Gather reST documentation from any source files
-- autorun: Execute code in a ``runblock`` directive
-- beamer_: A builder for Beamer (LaTeX) output.
-- blockdiag: embed block diagrams by using blockdiag_
-- cacoo: embed diagram from Cacoo
-- cf3domain: a domain for CFEngine 3 policies
-- cheader: The missing c:header directive for Sphinx's built-in C domain
-- cheeseshop: easily link to PyPI packages
-- clearquest: create tables from ClearQuest_ queries
-- cmakedomain_: a domain for CMake_
-- coffeedomain: a domain for (auto)documenting CoffeeScript source code
-- context: a builder for ConTeXt
-- disqus: embed Disqus comments in documents
-- documentedlist: converts a Python list to a table in the generated
-  documentation
-- doxylink: Link to external Doxygen-generated HTML documentation
-- domaintools_: A tool for easy domain creation
-- email: obfuscate email addresses
-- erlangdomain: an extension for Erlang support (Sphinx 1.0 needed)
-- exceltable: embed Excel spreadsheets into documents using exceltable_
-- feed: an extension for creating syndication feeds and time-based overviews
-  from your site content
-- findanything_: an extension to add Sublime Text 2-like findanything panels
-  to your documentation to find pages, sections and index entries while typing
-- gnuplot: produces images using gnuplot_ language
-- googleanalytics: track web visitor statistics by using `Google Analytics`_
-- googlechart: embed charts by using `Google Chart`_
-- googlemaps: embed maps by using `Google Maps`_
-- httpdomain: a domain for documenting RESTful HTTP APIs
-- hyphenator: client-side hyphenation of HTML using hyphenator_
-- imgur: embed Imgur images, albums, and metadata in documents
-- inlinesyntaxhighlight_: inline syntax highlighting
-- lassodomain: a domain for documenting Lasso_ source code
-- libreoffice: an extension to include any drawing supported by LibreOffice
-  (e.g. odg, vsd, ...)
-- lilypond: an extension inserting music scripts from Lilypond_ in PNG format
-- makedomain_: a domain for `GNU Make`_
-- matlabdomain: document MATLAB_ code
-- mockautodoc: mock imports
-- mscgen: embed mscgen-formatted MSC (Message Sequence Chart)s
-- napoleon: supports `Google style`_ and `NumPy style`_ docstrings
-- nicovideo: embed videos from nicovideo
-- nwdiag: embed network diagrams by using nwdiag_
-- omegat: support tools to collaborate with OmegaT_ (Sphinx 1.1 needed)
-- osaka: convert standard Japanese doc to Osaka dialect (this is a joke
-  extension)
-- paverutils: an alternate integration of Sphinx with Paver_
-- phpdomain: an extension for PHP support
-- plantuml: embed UML diagram by using PlantUML_
-- py_directive: Execute python code in a ``py`` directive and return a math
-  node
-- rawfiles: copy raw files, like a CNAME
-- requirements: declare requirements wherever you need (e.g. in test
-  docstrings), mark statuses and collect them in a single list
-- restbuilder: a builder for reST (reStructuredText) files
-- rubydomain: an extension for Ruby support (Sphinx 1.0 needed)
-- sadisplay: display SqlAlchemy model sadisplay_
-- sdedit: an extension inserting sequence diagram by using Quick Sequence
-  Diagram Editor (sdedit_)
-- seqdiag: embed sequence diagrams by using seqdiag_
-- slide: embed presentation slides on slideshare_ and other sites
-- swf_: embed flash files
-- sword: an extension inserting Bible verses from Sword_
-- tikz: draw pictures with the `TikZ/PGF LaTeX package`_
-- traclinks: create TracLinks_ to a Trac_ instance from within Sphinx
-- versioning: Sphinx extension that allows building versioned docs for
-  self-hosting
-- whooshindex: whoosh indexer extension
-- youtube: embed videos from YouTube_
-- zopeext: provide an ``autointerface`` directive for using `Zope interfaces`_
-
-
-See the :doc:`extension tutorials <../development/tutorials/index>` on getting
-started with writing your own extensions.
-
-
-.. _aafigure: https://launchpad.net/aafigure
-.. _gnuplot: http://www.gnuplot.info/
-.. _paver: https://paver.readthedocs.io/en/latest/
-.. _Sword: https://www.crosswire.org/sword/
-.. _Lilypond: http://lilypond.org/
-.. _sdedit: http://sdedit.sourceforge.net/
-.. _Trac: https://trac.edgewall.org/
-.. _TracLinks: https://trac.edgewall.org/wiki/TracLinks
-.. _OmegaT: https://omegat.org/
-.. _PlantUML: http://plantuml.com/
-.. _PyEnchant: https://pythonhosted.org/pyenchant/
-.. _sadisplay: https://bitbucket.org/estin/sadisplay/wiki/Home
-.. _blockdiag: http://blockdiag.com/en/
-.. _seqdiag: http://blockdiag.com/en/
-.. _actdiag: http://blockdiag.com/en/
-.. _nwdiag: http://blockdiag.com/en/
-.. _Google Analytics: https://www.google.com/analytics/
-.. _Google Chart: https://developers.google.com/chart/
-.. _Google Maps: https://www.google.com/maps
-.. _Google style: https://google.github.io/styleguide/pyguide.html
-.. _NumPy style: https://github.com/numpy/numpy/blob/master/doc/HOWTO_DOCUMENT.rst.txt
-.. _hyphenator: https://github.com/mnater/hyphenator
-.. _exceltable: https://pythonhosted.org/sphinxcontrib-exceltable/
-.. _YouTube: https://www.youtube.com/
-.. _ClearQuest: https://www.ibm.com/us-en/marketplace/rational-clearquest
-.. _Zope interfaces: https://zopeinterface.readthedocs.io/en/latest/README.html
-.. _slideshare: https://www.slideshare.net/
-.. _TikZ/PGF LaTeX package: https://sourceforge.net/projects/pgf/
-.. _MATLAB: https://www.mathworks.com/products/matlab.html
-.. _swf: https://bitbucket.org/klorenz/sphinxcontrib-swf
-.. _findanything: https://bitbucket.org/klorenz/sphinxcontrib-findanything
-.. _cmakedomain: https://bitbucket.org/klorenz/sphinxcontrib-cmakedomain
-.. _GNU Make: https://www.gnu.org/software/make/
-.. _makedomain: https://bitbucket.org/klorenz/sphinxcontrib-makedomain
-.. _inlinesyntaxhighlight: https://sphinxcontrib-inlinesyntaxhighlight.readthedocs.io/
-.. _CMake: https://cmake.org
-.. _domaintools: https://bitbucket.org/klorenz/sphinxcontrib-domaintools
-.. _restbuilder: https://pypi.org/project/sphinxcontrib-restbuilder/
-.. _Lasso: http://www.lassosoft.com/
-.. _beamer: https://pypi.org/project/sphinxcontrib-beamer/