jgm/pandoc: pandoc 2.3

Add --metadata-file option (Mauro Bieg, #1960), which allows users to specify metadata in a YAML file, regardless of the input format (#1960).

Text.Pandoc.Writers.Shared: export isDisplayMath (API change).

Text.Pandoc.Readers.Markdown: export yamlToMeta (API change, Mauro Bieg).

Text.Pandoc.Readers.LaTeX.Types:

• New type ArgSpec (API change).
• Second parameter of Macro constructor is now [ArgSpec] instead of Int (API change).

Markdown reader:

• Use tex instead of latex for raw tex-ish content. We can't always tell if it's LaTeX, ConTeXt, or plain TeX. Better just to use tex always. Note that if context or latex specifically is desired, you can still force that in a markdown document by using the raw attribute. Note that this change may affect some filters, if they assume that raw tex parsed by the Markdown reader will be RawBlock (Format latex). In most cases it should be trivial to modify the filters to accept tex as well.
• Refactor and reorganize YAML code (Mauro Bieg).
• Make example_lists work for interrupted lists without startnum (#4908).

HTML reader:

• Parse <script type="math/tex tags as math (#4877). These are used by MathJax in some configurations.
• Extract spaces inside links instead of trimming them (Alexander Krotov, #4845).
• Added round-trip tests (Alexander Krotov).
• Make parsing sensitive to the raw_tex extension (#1126). This now allows raw LaTeX environments, \ref, and \eqref to be parsed (which is helpful for translation HTML documents using MathJaX).

Org reader (Albert Krewinkel):

• Respect export option p for planning info. Inclusion of planning info (*DEADLINE*, *SCHEDULED*, and *CLOSED*) can be controlled via the p export option: setting the option to t will add all planning information in a Plain block below the respective headline.
• Org reader internals: don't rely on RecordWildCards and ViewPatterns ghc extensions.
• Strip planning info from output. Planning info is parsed, but not included in the output (as is the default with Emacs Org-mode, #4867).

LaTeX reader:

• Handle parameter patterns for \def (#4768, #4771). For example: \def\foo#1[#2]{#1 and #2}.
• Allow % characters in URLs. This affects \href and \url (#4832).
• Fixed parsing of \texorpdfstring. We were returning the wrong argument as the content.
• Support blockcquote, foreignblockquote, foreigncblockquote, hyphenblockquote, hyphencblockquote, enquote*, foreignquote, hyphenquote from csquotes (#4848). Note that foreignquote will be parsed as a regular Quoted inline (not using the quotes appropriate to the foreign language).
• Support more text-mode accents (#4652). Add support for \|, \b, \G, \h, \d, \f, \r, \t, \U, \i, \j, \newtie, \textcircled. Also fall back to combining characters when composed characters are not available.
• Resolve \ref for figure numbers.
• Support mintinline (#4365, Marc Schreiber).
• Fix siunitx unit commands so they are only recognized in siunitx contexts (#4842). For example, \l outside of an siunitx context should be l-slash, not l (for liter).
• Fix double unnumbered class (#4838). The unnumbered class was being included twice for starred sections.

RST reader: Don't skip link definitions after comments (#4860).

Muse reader (Alexander Krotov):

• Close the </quote> in indented tag test. There is already a separate test for unclosed </quote>.
• Autonumber sections in the correct order. Parsing now stops at each section header to ensure the header is registered before parsing of the next section starts.
• Move duplicate code into headingStart function.
• Allow newline after opening * or **.
• Don't allow digits after closing marker in lightweight markup This change makes reader more compatible with Emacs Muse.
• Parse <verse> tag in one pass instead of using parseFromString. This change makes it possible to have verbatim </verse> tag inside verse.

ODT reader: deal gracefully with missing <office:font-face-decls/> (#4336). This allows pandoc to parse ODT document produced by KDE's Calligra.

Muse writer (Alexander Krotov):

• Output headers without asterisks if not on the top level.
• Never wrap definition list terms.
• Set envInsideBlock = True when rendering notes.
• Use "" instead of [] for empty String.
• Check for whitespace in the beginning and end of Str's.
• Escape -, ; and > in the beginning of strings.
• Escape list markers in the beginning of notes.
• Normalize inline list before testing if tags should be used.
• Use tags instead of lightweight markup for empty strings.
• Use lightweight markup when possible.
• Escape empty strings. This guarantees that conditionalEscapeString never returns empty string.
• Wrap conditionalEscapeString result into Muse type. This removes the need to pass envInsideLinkDescription to it.
• Separate shouldEscapeString function.
• Simplify inline list rendering.
• Replace newlines in strings with spaces.

Docx writer:

• Add MetaString case for abstract, subtitle (#4900, Mauro Bieg).
• Properly handle display math in spans (#4826). This isn't a complete solution, since other nestings of display math may still cause problems, but it should work for what is by far the most common case.

HTML writer:

• Always output <dt> element, even if it is empty (#4883, Alexander Krotov).
• Don't prefix epub: attributes with data-.

Org writer: Don't escape literal _, ^ (#4882). Org doesn't recognize these escapes.

ODT writer: Fix percentage image scaling (#4881, Nils Carlson). Image scaling was broken when a width was set to a percentage.

EPUB writer: set epub:type on body element in each chapter, depending on the epub:type of the first section (#4823). This only affects epub3. See http://www.idpf.org/epub/profiles/edu/structure/#h.l0bzsloklt10

FB2 writer: put coverpage element between title and date rather than in document-info element (#4854).

Markdown writer: Escape ~ if strikeout extension enabled (#4840).

Haddock writer: Use proper format for latex math in haddock (#4571, Joe Hermaszewski). Inline math in \(..\), display math in \[..\], tex is now used. Previously we'd "fake it with unicode" and fall back to tex when that didn't work. But newer haddock versions support latex math.

TEI writer:

• Ensure that title element is always present, even if empty (#4839).
• Put author tags in the template, rather than adding them in the writer (#4839).

LaTeX writer/template: be sensitive to filecolor variable (#4822). linkcolor only affects internal links, and urlcolor only affects linked URLs. For external links, the option to use is filecolor.

ConTeXt writer: output raw tex blocks as well as context (#969).

RST writer:

• Use .. raw:: latex for tex content.
• Use .. container for generic Divs, instead of raw HTML.
• Render Divs with admonition classes as admonitions (#4833). Also omit Div with class admonition-title. These are generated by the RST reader and should be omitted on round-trip.

Text.Pandoc.PDF: fix message printed when rsvg-convert is not available (#4855, Antonio Terceiro).

HTML5 template: add the title-block-header identifier to the header element, to make it easier to style precisely (#4767, J. B. Rainsberger).

OpenDocument template: Remove unnecessary indenting of TOC title (#4798, José de Mattos Neto).

latex template: Add support for (toc-title) to LaTeX (and PDF) (#4853, Wandmalfarbe).

TEI template: improve publicationStmt. Add support for publisher, address, pubPlace, and date variables.

beamer template: Support "toc-title" (#4835, Cyril Roelandt).

Text.Pandoc.Extensions: Fix haddock on Ext_footnotes (Chris Martin).

Lua: cleanup Lua utils, remove unused functions (Albert Krewinkel).

MANUAL.txt:

• Clarify that --biblatex/--natbib don't work directly for PDF (#4904).
• Document epub:type attribute (Mauro Bieg, #4901)
• Clarify when --resource-path has an effect.
• More detail on customization in syntax highlighting section.
• Document encoding issue with --listings (#4871, Damien Clochard).
• Remove docs on removed --katex-stylesheet (Mauro Bieg, #4862).
• Use https for context wiki links (#4910).

CONTRIBUTING.md:

• Link to lua-filters repository (#4874).
• Fix mistake in REPL instructions for stack. (#4849, Brian Leung).

lua-filters.md: add links to filters, and to lua-filters repository (#4874).

INSTALL.md:

• Indicate that cabal >= 2.0 is needed.
• Added chocolatey installation method (#4844, Miodrag Milić).

Travis: exclude round-trip tests, except for nightly test which can fail.

Use latest texmath, pandoc-citeproc.

Use a patched version of foundation until https://github.com/haskell-foundation/foundation/pull/503 is fixed.

Clean up appveyor build and Windows package creation. We now use 64-bit stack and ghc 8.4.3, lts-12 for the 64-bit build. The WiX-based msi is now 64-bit for 64-bit builds (fixing #4795).

Remove obsolete RELEASE-CHECKLIST.md.

Added additional compiler warnings in Makefile and CI builds.