Update asciidoctor-pdf requirement from 1.6.0 to 2.1.0

[dependabot]

Updates the requirements on asciidoctor-pdf to permit the latest version.

Release notes

Sourced from asciidoctor-pdf's releases.

v2.1.0

We did it! We got beyond the Asciidoctor PDF 2.0 release. This is the first minor release in the Asciidoctor PDF 2 release line. This release introduces the long-awaited support for multiple columns on the document body, which is activated using the page-columns theme key. This version also brings support for scaling images relative to the intrinsic width using either the scale attribute or the pdfwidth attribute expressed using a value with the iw unit. Support for text formatting on the index term is honored when the term is displayed in the index. You can avoid a page break between the part and its first chapter by setting the heading-part-break-after theme key to avoid. Finally, a bibliography entry now includes a backlink to the first reference to it in the body of the document.

During the development of this release, numerous bugs were founds and fixed, which have all been backported to the 2.0.x branch and included in the 2.0.8 release.

Don't forget that there are loads of examples of how to extend the converter to customize it to suit your specific publishing needs. See https://docs.asciidoctor.org/pdf-converter/latest/extend/use-cases/

Distribution

• RubyGem (asciidoctor-pdf)

Changelog

Enhancements

• arrange body of article or manpage doctype into multiple columns if page-columns key is set in theme (#327)
• allow column gap to be specified using page-column-gap key (#327)
• introduce convert_index_categories method to handle rendering of categories for index inside column box (#327)
• rename convert_index_list method to convert_index_term to make its purpose more clear (#327)
• add save_theme helper to work with a copy of the theme within a scope (#2196)
• add support for scale attribute or iw unit on pdfwidth attribute on image macros (#1933)
• add backlink from bibref on bibliography entry to first reference to that entry in the document (#1737)
• preserve text formatting on index term in index section (#897)
• don't insert page break between part and first chapter if heading-part-break-after key in theme is avoid (#1795)

Release meta

Released on: 2022-06-10 Released by: @​mojavelinux Release beer: Atomic Torpedo by Sierra Nevada Brewing Co.

Logs: resolved issues | full diff

Credits

A very special thanks to all the awesome supporters of the Asciidoctor OpenCollective campaign, who provide critical funding for the ongoing development of this project.

Changelog

Sourced from asciidoctor-pdf's changelog.

== 2.1.0 (2022-06-11) - @​mojavelinux

Enhancements::

• arrange body of article or manpage doctype into multiple columns if page-columns key is set in theme (#327)
• allow column gap to be specified using page-column-gap key (#327)
• introduce convert_index_categories method to handle rendering of categories for index inside column box (#327)
• rename convert_index_list method to convert_index_term to make its purpose more clear (#327)
• add save_theme helper to work with a copy of the theme within a scope (#2196)
• add support for scale attribute or iw unit on pdfwidth attribute on image macros (#1933)
• add backlink from bibref on bibliography entry to first reference to that entry in the document (#1737)
• preserve text formatting on index term in index section (#897)
• don't insert page break between part and first chapter if heading-part-break-after key in theme is avoid (#1795)

=== Details

{url-repo}/releases/tag/v2.1.0[git tag] | {url-repo}/compare/v2.0.8...v2.1.0[full diff]

== 2.0.8 (2022-06-08) - @​mojavelinux

Improvements::

• encapsulate logic to adjust column box inside float and dry run
• automatically set height on column box if not specified; update value automatically when reflowing margins

Bug Fixes::

• correctly compute value of to cursor on extent when column box starts below top of page (#2230)
• fix crash in ColumnBox#move_past_bottom when :reflow_margins option is not set
• fix x position of SVG when advanced to next column of column box
• at_page_top? should consider top of column box to be top of page
• prevent SVG image taller than column from being advanced to next column
• don't push section that follows index section in article to new page if last page of index does not extend to bottom of page

=== Details

{url-repo}/releases/tag/v2.0.8[git tag] | {url-repo}/compare/v2.0.7...v2.0.8[full diff]

== 2.0.7 (2022-06-03) - @​mojavelinux

Improvements::

• don't recommend prawn-gmagick if PNG or JPG is corrupt or incomplete
• add helper method to determine when to recommend the prawn-gmagick gem

Bug Fixes::

• fix crash when doctitle or section title with automatic ID contains inline image without explicit width (#2228)
• use prawn-gmagick, if available, to read raster image referenced by SVG (#2223)
• allow image path in SVG to refer to any location within Asciidoctor jail (no restriction if safe mode is unsafe) (#1941)

... (truncated)

Commits

• f9a7bdf release 2.1.0 [no ci]
• 3405888 minor revisions to what's new page
• 819e89f fix docs version [skip ci]
• f6fea0b update What's New page for Asciidoctor PDF 2.1.0 release (PR #2240)
• 49dbf39 add missing CHANGELOG entry for #897
• ebcf568 fix flakey test
• 5b3087a resolves #1795 don't insert page break between part and first chapter if head...
• 314c56d fix warning on Ruby 2.7
• f4bd057 resolves #327 arrange body of article or manpage doctype into multiple column...
• 8d25b99 resolves #897 preserve text formatting in display of index term (PR #2238)
• Additional commits viewable in compare view

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[dependabot]

Superseded by #172.