Format - cell, alignment tab

Change-Id: I78e4252064671720d41ad3af086b41d2efe06ac1
Reviewed-on: https://gerrit.libreoffice.org/2773Tested-by: Caolán McNamara <caolanm@redhat.com>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>