A new callback has been introduced for notifying the client:
LOK_CALLBACK_CELL_ADDRESS

Change-Id: I40b38a3cb8fb658c3f00332d56cfcbaf98e13771
Reviewed-on: https://gerrit.libreoffice.org/37357Reviewed-by: pranavk <pranavk@collabora.co.uk>
Tested-by: pranavk <pranavk@collabora.co.uk>