[GNU ELPA] Ef-Themes version 0.10.0

[ELPA update]

Version 0.10.0 of package Ef-Themes has just been released in GNU ELPA.
You can now find it in M-x list-packages RET.

Ef-Themes describes itself as:

  ===========================
  Colorful and legible themes
  ===========================

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

## Summary:

  # Ef (εὖ) themes for GNU Emacs

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

  The `ef-themes` are a collection of light and dark themes for GNU Emacs
  whose goal is to provide colorful ("pretty") yet legible options for
  users who want something with a bit more flair than the `modus-themes`
  (also designed by me).  Watch the presentation, which demonstrates each
  of the eight themes in the collection:
  <https://protesilaos.com/codelog/2022-08-18-ef-themes-demo/>.

## Recent NEWS:

                     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                      CHANGE LOG OF THE EF THEMES
                     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━


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

The newest release is at the top.  For further details, please consult
the manual: <https://protesilaos.com/emacs/ef-themes>.


Version 0.10.0 on 2022-12-02
════════════════════════════

New user option for highlighted region
──────────────────────────────────────

  The `ef-themes-region' accepts a list of symbols that affect how the
  region looks.  The manual or the variable's doc string describe the
  technicalities.  Here is a sample:

  ┌────
  │ (setq ef-themes-region '(intense no-extend))
  └────

  Remember that changes to theme user options must be done before
  loading a theme.  For any subsequent customisation, a theme re-load is
  required.


The `ef-themes-headings' now affects the Org agenda
───────────────────────────────────────────────────

  Before, the Org agenda headings would inherit from the generic heading
  levels 0 and 1.  This had undesired effects, as users often need a
  taller typeface for prose (e.g. regular Org files), though not
  necessarily for viewing their already well-structured Org agenda.

  The `ef-themes-headings' can now control the Org agenda date and
  structure headings directly.  A complete example:

  ┌────
  │ (setq ef-themes-headings ; read the manual's entry or the doc string
  │       '((0 . (variable-pitch light 1.9))
  │     (1 . (variable-pitch light 1.8))
  │     (2 . (variable-pitch light 1.7))
  │     (3 . (variable-pitch semilight 1.6))
  │     (4 . (variable-pitch semilight 1.5))
  │     (5 . (variable-pitch regular 1.4))
  │     (6 . (variable-pitch regular 1.3))
  │     (7 . (variable-pitch 1.2))    ; absence of weight means `bold'
  │     (agenda-date . (semilight 1.5))
  │     (agenda-structure . (variable-pitch light 1.9))
  │     (t . (variable-pitch 1.1))))
  └────

  In Org agenda buffers, the "structure" is the type of heading that
  describes the current block of content.  In the generic agenda, it is
  the first line, which reads something like `Week-agenda (W48):'.

  Note that Org re-uses heading levels past 8.  This is not the theme's
  work, so heading 9 looks the same as 1.  Check the user options
  `org-level-faces', `org-n-level-faces' for ways to change this.


Support for more packages
─────────────────────────

  ⁃ cider
  ⁃ clojure-mode
  ⁃ eglot
  ⁃ perspective.  Thanks to Walheimat for the contribution.  This was
    done in pull request 18 on the GitHub mirror:
    <https://github.com/protesilaos/ef-themes/pull/18>.  The change is
    below the ~15 line limit.  It does not require copyright assignment
    to the Free Software Foundation.
  ⁃ tree-sitter


Lots of small tweaks to colour values
─────────────────────────────────────

  All themes have enjoyed attention to their details.  The general idea
  is that some colours are fine-tuned to look better in their context.
  In most cases, the change is subtle and can only be noticed when
  comparing samples side-by-side.  Some more noticeable effects:

  ⁃ All neutral backgrounds that are used for elements such as the
    `tab-bar-mode', the `header-line', the mode lines, and the like, are
    all amplified.  They should now be easier to discern, especially on
    monitors with inaccurate reproduction of grey values.

  ⁃ The `match' face, which is used by Grep, Occur, and related, now
    uses a coloured background instead of a neutral grey.  This makes it
    easier to stand out.  The choice of colour is consistent with the
    backgrounds used by Isearch for the current and other matches: they
    do not clash (e.g. a user may perform a search inside an Occur
    buffer).

  ⁃ The `M-x calendar' weekdays and weekends are rendered in distinct
  …  …