fdo#47302: Added insert->fields->page title button

Change-Id: Iebc8298a7e6a7d423d2667eec8a46a936cc4d2cd
Reviewed-on: https://gerrit.libreoffice.org/11599
Reviewed-by: Samuel Mehrbrodt <s.mehrbrodt@gmail.com>
Tested-by: Samuel Mehrbrodt <s.mehrbrodt@gmail.com>