Some fixups

Make the example work again, fix volume on OS X

Change-Id: I7730213838666eba10317ccbe0b2a759192e829f
Reviewed-by: Laurent Montel <laurent.montel@kdab.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@theqtcompany.com>
Add some more Q_DECL_OVERRIDE

Change-Id: I3b0a4054e3fda5940c58de5a123eda67928a8fd6
Reviewed-by: Laurent Montel <laurent.montel@kdab.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@theqtcompany.com>
Fix tab order and buddies in example

Change-Id: If5a74111e87889c4790ed0996a37e6f20b1ce0af
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@theqtcompany.com>
Add emit methods to emit signals when speech properties change.

Use new emit methods in unix backends when properties change.

Change-Id: I8245baaf159603051603141692633c843e1c08ed
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@theqtcompany.com>