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/2020-04-ebuyclub-com-economiser-grace-a-du-cashback/index.md

@@ -6,9 +6,10 @@ slug: "ebuyclub-com-economiser-grace-a-du-cashback"
 wordpress_id: 515
 excerpt: "Nous avons déjà parlé d’extensions pour économiser ou trouver des coupons de réductions en ligne, de banques de…\n"
 featured_image: ""
-author: {"id":2,"name":"Expert"}
-categories: [{"id":14,"name":"Informatique","slug":"informatique"}]
+author: "Expert"
+categories: ["Informatique"]
 tags: []
+section: "informatique"
 ---
 
 <p><!--kg-card-begin: html--></p>