refactor: update content structure and layout templates

- Updated author format in content files
- Added section field to content files
- Simplified categories format
- Removed no-category.html layout
- Updated list.html and single.html layouts
- Updated index.html layout
- Updated generate-content.js script
- Do not index content with git

content/informatique/2020-09-bitwarden-rust/index.md

@@ -6,9 +6,10 @@ slug: "bitwarden-rust"
 wordpress_id: 603
 excerpt: "Jusqu’à il a trois semaines je n’utilisais pas de gestionnaire de mot de passe (ou du moins presque).…\n"
 featured_image: "https://www.mistergeek.net/wp-content/uploads/2020/12/bitwarden.jpg"
-author: {"id":1,"name":"Kevin"}
-categories: [{"id":14,"name":"Informatique","slug":"informatique"}]
+author: "Kevin"
+categories: ["Informatique"]
 tags: []
+section: "informatique"
 ---
 
 </p>