fdo#87185 add icon to Format > Image and it context menu entry

Change-Id: I92753406e500b58c6cf8de755eee91ea577b68a8
Reviewed-on: https://gerrit.libreoffice.org/13493
Reviewed-by: Yousuf Philips <philipz85@hotmail.com>
Tested-by: Yousuf Philips <philipz85@hotmail.com>