add community guides / showcase

[madjin]

Something like this for showing videos / content about tutorials and guides made by the community: https://docusaurus.io/showcase

• https://vimeo.com/roustan
• https://www.youtube.com/watch?v=Xrrt0rAcMXg&t=1s&pp=ygURdm94dmllbm5lIGh5cGVyZnk%3D
• https://www.youtube.com/watch?v=_-UCLWxU8cU&t=626s&pp=ygURdm94dmllbm5lIGh5cGVyZnk%3D
• https://www.youtube.com/watch?v=DrXFpepPvoE&pp=ygURdm94dmllbm5lIGh5cGVyZnk%3D
• https://www.youtube.com/watch?v=sUOXYk91AY8&t=2998s&pp=ygURdm94dmllbm5lIGh5cGVyZnk%3D