py-sphinx: updated to 2.3.1

Release 2.3.1:

Bugs fixed
* sphinx-autogen: raises AttributeError

Release 2.3.0:

Incompatible changes
* end-before option of literalinclude directive does not match the first line of the code block.
* Change default User-Agent header to "Sphinx/X.Y.Z requests/X.Y.Z python/X.Y.Z". It can be changed via user_agent.
* text: content of admonitions starts after a blank line

Deprecated
sphinx.builders.gettext.POHEADER
sphinx.io.SphinxStandaloneReader.app
sphinx.io.SphinxStandaloneReader.env
sphinx.util.texescape.tex_escape_map
sphinx.util.texescape.tex_hl_escape_map_new
sphinx.writers.latex.LaTeXTranslator.no_contractions

Features added
* C++, support bit-fields.
* html: Eliminate prompt characters of doctest block from copyable text
* html: Use favicon for OpenSearch if available
* html theme: agogo theme now supports rightsidebar option
* Add PEP-561 Support
* latex: Allow to load additonal LaTeX packages via extrapackages key of latex_elements
* Add new config variable: user_agent
* LaTeX: have backslash also be an inline literal word wrap break character
* LaTeX: Support upLaTeX as a new latex_engine (experimental)
* Improve a warning message when extensions are not parallel safe
* Improve Intersphinx performance for multiple remote inventories.
* apidoc: .so file support
* autosummary: emit autodoc-skip-member event on generating stub file
* i18n: make explicit titles in toctree translatable
* linkcheck: Add linkcheck_auth option to provide authentication information when doing linkcheck builds
* linkcheck: Handles HTTP 308 Permanent Redirect
* html: Wrap section number in span tag
* gettext: Add gettext_last_translator' and :confval:`gettext_language_team to customize headers of POT file

Bugs fixed
* LaTeX: Longtable before header has incorrect distance (refs: latex3/latex2e#173)
* LaTeX: Avoid section names at the end of a page
* LaTeX: Do not replace unicode characters by LaTeX macros on unicode supported LaTeX engines: ¶, §, €, ∞, ±, →, ‣, –, superscript and subscript digits go through “as is” (as default OpenType font supports them)
* linkcheck: Be defensive and handle newly defined HTTP error code
* linkcheck: Failure on parsing content
* image URLs containing data: causes gettext builder crashed
* i18n: Error when compiling message catalogs on Hindi
* i18n: KeyError is raised if section title and table title are same
* i18n: rst_prolog breaks the translation
* mathbase: Some deprecated functions have removed
* autodoc: mock object does not work as a class decorator
* epub: Wrong internal href fragment links
* Allow not to install sphinx.testing as runtime (mainly for ALT Linux)
* html: search result was broken with empty html_file_suffix
* LaTeX does not wrap long code lines at backslash character
* LaTeX: PDF build breaks if admonition of danger type contains code-block long enough not to fit on one page
* LaTeX: code-block in a danger type admonition can easily spill over bottom of page
* texinfo: Code examples broken following “sidebar”
* An orphan warning is emitted for included document on Windows. Thanks to @drillan
* Fix smartypants module calls re.sub() with wrong options
* HTML search: If a search term is partially matched in the title and fully matched in a text paragraph on the same page, the search does not include this match.
* config.py shouldn’t pop extensions from overrides
* text: extra spaces are inserted to hyphenated words on folding lines
* LaTeX: xelatex converts straight double quotes into right curly ones (shows when smartquotes is False)
* LaTeX: even with smartquotes off, PDF output transforms straight quotes and consecutive hyphens into curly quotes and dashes
* LaTeX: multi-line display of authors on title page has ragged edges
* Sphinx crashes with docutils-0.16b0
* sphinx-build: A console message is wrongly highlighted
* sphinx-build: -D option does not considers 0 and 1 as a boolean value

(adam)