Convert chart::InsertTitleDlg to .ui

Change-Id: Ic92ab5e715253caa4be9c0fea4499797ed2b7485
Reviewed-on: https://gerrit.libreoffice.org/6997
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>