[TASK] Add "action-edit-download" sprite icon

Brings an icon for download action. Icon is based on the
action-edit-upload sprite icon.

Change-Id: I4327c85c14dea3b69d8184259c5ac8729396d2e8
Resolves: #55594
Releases: 6.2
Reviewed-on: https://review.typo3.org/27266
Reviewed-by: Cedric Ziel
Tested-by: Cedric Ziel
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
[TASK] Style "Download" button - element information

Brings button style to "Download" link with download icon.

Change-Id: I4edae8b861d9c6f98f156d8b538031dd8ca8f62c
Resolves: #55597
Releases: 6.2
Reviewed-on: https://review.typo3.org/27267
Reviewed-by: Marcin Sągol
Tested-by: Marcin Sągol
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters