Unify wizards with TOC and cancel button.

QTBUG-28385 is biting us over and over (QWizard doesn't have close
button nor cancel button on Mac in Qt 5), and actually there's no reason
for us having a wizard without the features from Utils::Wizard.

Task-number: QTCREATORBUG-10346
Task-number: QTBUG-28385
Change-Id: I80c0d82fe6738496c2ac03c31a1c2757ade8e266
Reviewed-by: Jarek Kobus <jaroslaw.kobus@digia.com>
Reviewed-by: Daniel Teske <daniel.teske@digia.com>