fdo#86086 addition of number format submenu and simplifying items

Change-Id: Ic65cb86872241b0b9425e65883a75b1e7382522e
Reviewed-on: https://gerrit.libreoffice.org/12367
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>