[FEATURE] sys_note: Display/functionality for hover/context menu

In page-module content-elements only show icons when hovered
and they have a contextmenu on the icon.

Add same functionality for sys_note

Change-Id: I170309ac5ffe8b9cfa25ba1c9933d69ddcbcbca8
Resolves: #43496
Releases: 6.1
Reviewed-on: https://review.typo3.org/16911
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn