copy conditional formatting for single cells, fdo#82503

Change-Id: I22f239fbbbfa3ac562b860efb990dff10d0e0e24
Reviewed-on: https://gerrit.libreoffice.org/10942
Reviewed-by: David Tardon <dtardon@redhat.com>
Tested-by: David Tardon <dtardon@redhat.com>