Update to modus-themes version 3.0.0

Update to modus-themes version 3.0.0

* doc/misc/modus-themes.org
(Option for red-green color deficiency or deuteranopia)
(Option for more bold constructs, Option for more italic constructs)
(Option for font mixing, Option for box buttons)
(Option for mode line presentation)
(Option for accented background in tab interfaces)
(Option for completion framework aesthetics, Option for mail citations)
(Option for line numbers, Option for mouseover effects)
(Option for diff buffer looks, Option for org-mode block styles)
(Option for Org agenda constructs)
(Option for the headings' overall style)
(Option for variable-pitch font in UI elements, Note on SHR fonts):
Revise markup of "non-nil" so that it is rendered properly in texinfo.

(Option for fringe visibility, Option for line highlighting): Reword
description of user option.

(Full support for packages or face groups): Update list of supported
packages or face groups.

(Note on ERC escaped color sequences)
(What is the best setup for legibility?)
(Port the Modus themes to other platforms?): Prefer American English.

(Note on pdf-tools link hints): Use double spacing between sentences

(Acknowledgements): Update list of names that have contributed to the
project, which was user feedback in this case.

* etc/themes/modus-themes.el (modus-themes, modus-themes-faces):
Reword doc string.
(modus-themes--version): Update to current version.
(modus-themes-version): Refine function definition.
(modus-themes-completion-standard-first-match)
(modus-themes-completion-standard-selected)
(modus-themes-completion-extra-selected)
(modus-themes-completion-key-binding, modus-themes-intense-markup)
(modus-themes--heading-weights, modus-themes--completion): Delete
obsolete forms, which were deprecated many months/version ago.
(modus-themes-fringes, modus-themes-completions)
(modus-themes-hl-line): Update default value and reword doc string
accordingly.
(modus-themes-faces): Update list of supported faces and their
attributes.

* etc/themes/modus-operandi-theme.el:
* etc/themes/modus-vivendi-theme.el: Update version header.

Complete release notes: <https://protesilaos.com/codelog/2022-10-28-modus-themes-3-0-0/>.