Add Vitepress docs (#326)

* Add vitepress for docs

* some fix

* Use vitepress and update docs

* Use vitepress and update docs

* Update README.md

* Add favicon

* Add docs by @jiriks74

Co-authored-by: jiriks74 <jiri@stefka.eu>

---------

Co-authored-by: jiriks74 <jiri@stefka.eu>

docs/usage/init-via-git.md

@@ -39,4 +39,4 @@ To http://localhost:6157/init
  * [new branch]      master -> master
 ```
 
-https://github.com/thomiceli/opengist/assets/27960254/3fe1a0ba-b638-4928-83a1-f38e46fea066
+<video controls="controls" src="https://github.com/thomiceli/opengist/assets/27960254/3fe1a0ba-b638-4928-83a1-f38e46fea066" />