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/streaming/2017-06-5-sites-streaming/index.md

@@ -6,9 +6,10 @@ slug: "5-sites-streaming"
 wordpress_id: 161
 excerpt: "Vous recherchez un site de streaming ? Vous souhaitez regardes des films, des séries ou encore des animes…\n"
 featured_image: "https://www.mistergeek.net/wp-content/uploads/2017/06/top-site-streaming.jpg"
-author: {"id":1,"name":"Kevin"}
-categories: [{"id":10,"name":"Streaming","slug":"streaming"}]
+author: "Kevin"
+categories: ["Streaming"]
 tags: []
+section: "streaming"
 ---
 
 </p>