[GNU ELPA] Modus-Themes version 4.2.0

[ELPA update]

Version 4.2.0 of package Modus-Themes has just been released in GNU ELPA.
You can now find it in M-x list-packages RET.

Modus-Themes describes itself as:

  ===============================================
  Elegant, highly legible and customizable themes
  ===============================================

More at https://elpa.gnu.org/packages/modus-themes.html

## Summary:

  # Modus themes for GNU Emacs

  IMAGES HERE: <https://protesilaos.com/emacs/modus-themes-pictures>.

  Highly accessible themes, conforming with the highest standard for
  colour contrast between background and foreground values (WCAG AAA).
  They also are optimised for users with red-green colour deficiency.

  The themes are very customisable and provide support for a very wide
  range of packages.  Their manual is detailed so that new users can get
  started, while it also provides custom code for all sorts of more
  advanced customisations.

## Recent NEWS:

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              CHANGE LOG OF THE MODUS THEMES FOR GNU EMACS
             ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━


This document contains the release notes that are included in each
tagged commit on the project's main git repository:
<https://git.sr.ht/~protesilaos/modus-themes>.

The newest release is at the top.  Since the notes are meant to be in
plain text format, I copy them verbatim.

For further details, please consult these additional resources:

Manual
      <https://protesilaos.com/emacs/modus-themes>
Screenshots
      <https://protesilaos.com/emacs/modus-themes-pictures>


4.2.0
═════

I won a Google award for the Modus themes
─────────────────────────────────────────

  Report here:
  <https://protesilaos.com/codelog/2023-05-25-emacs-google-award/>.

  This is not a "change" per se, but it is worth documenting here.  It
  shows how important accessibility can be in empowering people to use
  their computer and, in our case, to exercise their software freedoms.

  The Modus themes tend to one aspect of accessibility.  They do not
  exhaust the topic, though they should at least raise awareness about
  the significance of tending to the usability needs of everyone.  The
  effort I put into documenting the themes (and my other packages)
  should be understood in this light as a means of helping people enjoy
  their software freedom by learning how to use and extend the program
  in question.


New tritanopia-optimised themes
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  I have created a pair of light and dark themes that are intended for
  people with blue-yellow colour deficiency (tritanopia).  These are
  `modus-operandi-tritanopia' (light) and `modus-vivendi-tritanopia'
  (dark).  Screenshots of all the Modus themes are available on my
  website: <https://protesilaos.com/emacs/modus-themes-pictures>.

  The entire collection is now described in the manual as follows:

        The Modus themes consist of eight themes, divided into
        four subgroups.

        Main themes
              `modus-operandi' is the project's main light theme,
              while `modus-vivendi' is its dark counterpart.
              These two themes are part of the project since its
              inception.  They are designed to cover a broad range
              of needs and are, in the opinion of the author, the
              reference for what a highly legible "default" theme
              should look like.

        Tinted themes
              `modus-operandi-tinted' and `modus-vivendi-tinted'
              are variants of the two main themes.  They slightly
              tone down the intensity of the background and
              provide a bit more color variety.
              `modus-operandi-tinted' has a set of base tones that
              are shades of light ochre (earthly colors), while
              `modus-vivendi-tinted' gives a night sky impression.

        Deuteranopia themes
              `modus-operandi-deuteranopia' and its companion
              `modus-vivendi-deuteranopia' are optimized for users
              with red-green color deficiency.  This means that
              they do not use red and green hues for color-coding
              purposes, such as for diff removed and added lines.
              Instead, they implement colors that are discernible
              by users with deueteranopia or deuteranomaly (mostly
              yellow and blue hues).

        Tritanopia themes
              `modus-operandi-tritanopia' and its counterpart
              `modus-vivendi-tritanopia' are optimized for users
              with blue-yellow color deficiency.  The idea is the
              same as with the deuteranopia variants: color coding
              relies only on hues that are accessible to people
              with tritanopia or tritanomaly, namely, shades of
              red and cyan.


Recalibrated the "graph" colours in all themes
──────────────────────────────────────────────

  The new palette subset improves the contrast of all the relevant
  colours when presented side-by-side.  These are most notably used by
  the `org-habit' consistency graph, which is displayed in the Org
  agenda.  The deuteranopia and tritanopia themes have their own bespoke
  …  …