Multiple fixes

Each commit is self-contained, so can be checked by itself. Changes can be grouped into:

Structure

• Redirect /about to /about/history. So far it has been an empty page:
• Remove /pages/donations page, which is a duplicate of the more updated /donations.
• Remove /pages/artist-interviews, which looks like a duplicate of /artist-interviews, but keep its introduction line in the interview list page at /categories/artist-interview:
• Redirect /artist-interviews to the interview list page.

Content, layouts, and styles

• Align download icons on home page center vertically:

• Bump hugo-kde up to have a better color mode selector:

• Update the interview part in home layout:
  • Cut "Could you tell us something about yourself? " off summaries:
  • Just use .Date.Year instead of manually mangling the file path.
• Put that interview part into a partial and use the partial on the interview list page;
• The interview list page lists all (instead of only the first 50) interviews in a paginated view, each view has 10 items:
• Move css in shop-item and support-krita-callout shortcodes to scss file;
• Stop using baseURL in layout components, which can easily lead to wrong URLs;
• Correct a string name on /donations page.

Management stuff

• Cleanup config.yaml;
• Add just commands;