Docs refactor (#9545)

* Refactor / reognaize docs structure

* Refactor plugin docs structure

* More refactoring / cleanup

* Update build images

* Gallery updates

* Order images

* Update part docs

* Settings images

* Stock images

* Reitntroduce gallery

* Add custom icon macro

* Update icons

* Cleanup

* Fix link

* Fix internal links

* Revert some page moves

* Fix links

* Fix links

docs/_includes/overrides/404.html

@@ -20,8 +20,7 @@
   <div class="md-grid md-typeset">
     <div class="mdx-hero"></div>
       <h1>
-        <span class='fas fa-search'></span>
-        Page not found
+        <i class="ti ti-search"></i> Page not found
       </h1>
   </div>
 </section>