Update project config to add cover page, log, favicon and improve output

Add a (symlinked) logo and cover image for HTML and EPUB output.
Add an author, so that metadata is set properly for EPUB.
Extend copyright statement by reusing information and adding links to
project and license.
Format today as YYYY-MM-DD instead of language specific.
Add a dummy favicon file based on the asymmetric key SVGs.

Signed-off-by: David Runge <dave@sleepmap.de>

.reuse/dep5

@@ -3,11 +3,11 @@ Upstream-Name: notes
 Upstream-Contact: Heiko Schaefer <heiko@schaefer.name>
 Source: https://codeberg.org/openpgp/notes
 
-Files: book/source/diag/*.png  book/source/diag/*.svg
+Files: book/source/diag/*  book/source/drawio/* book/source/_static/epub/img/* book/source/_static/html/img/*
 Copyright: 2023  The "Notes on OpenPGP" project
 License: CC-BY-SA-4.0
 
-Files:  book/source/drawio/* book/input/09-sigtree.md book/source/mermaid/*.png
+Files: book/input/09-sigtree.md book/source/mermaid/*.png
 Copyright: 2023  The "Notes on OpenPGP" project
 License: CC-BY-SA-4.0
 

book/source/conf.py

@@ -6,12 +6,20 @@
 # For the full list of built-in configuration values, see the documentation:
 # https://www.sphinx-doc.org/en/master/usage/configuration.html
 
+from datetime import date
+
 # -- Project information -----------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
 
 project = 'OpenPGP for application developers'
-copyright = '2023, The "Notes on OpenPGP" project, CC-BY-SA-4.0'
-version = "0.01"
+author = 'The "Notes on OpenPGP" project'
+upstream_url = "https://codeberg.org/heiko/openpgp-notes"
+license_url = "https://creativecommons.org/licenses/by-sa/4.0/"
+copyright = f'{date.today().year}, <a href="{upstream_url}">{author}</a>, <a href="{license_url}">CC-BY-SA-4.0</a>'
+version = "0.1"
+suppress_warnings = [
+    'epub.unknown_project_files',
+]
 
 # -- General configuration ---------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
@@ -29,6 +37,9 @@ numfig = True
 # number figures in flat hierarchy
 numfig_secnum_depth = 0
 
+# format today as YYYY-MM-DD instead of language specific
+today_fmt = "%Y-%m-%d"
+
 # -- Options for MyST-parser -------------------------------------------------
 # https://myst-parser.readthedocs.io/en/latest/configuration.html
 
@@ -45,6 +56,8 @@ myst_enable_extensions = [
 # -- Options for EPUB output -------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-epub-output
 
+epub_copyright = f'{date.today().year}, {author} ({upstream_url}), CC-BY-SA-4.0'
+epub_cover = ('_static/epub/img/cover.svg', 'cover.j2')
 epub_css_files = [
     'epub/css/custom.css'
 ]
@@ -58,9 +71,11 @@ html_css_files = [
     ('html/css/custom.css', {'priority': 1000})
 ]
 
+html_favicon = '_static/html/img/favicon.ico'
+html_logo = '_static/html/img/logo.svg'
 html_show_sphinx = False
-html_show_copyright = False
 html_show_sourcelink = False
+html_title = project
 
 # https://github.com/sphinx-doc/alabaster/blob/0.x/alabaster/theme.conf
 html_theme_options = {