[ACA] Context menu - support nested sub menus (#715)

* remove ContextMenuItemDirective

* remove custom menu animation

* remove custom menu styling

* menu item component

* material menu trigger

* clean up menu theme

* update context menu module

* remoe context menu from libraries document list

* clean up

* clean up

* tests

src/app/components/libraries/libraries.component.html

@@ -18,7 +18,6 @@
         <div class="inner-layout__panel">
             <adf-document-list #documentList
                 acaDocumentList
-                acaContextActions
                 [display]="documentDisplayMode$ | async"
                 currentFolderId="-mysites-"
                 selectionMode="single"