Add a new BINDABLE declaration to the Q_PROPERTY() macro that tells moc
where to find the QBindable for the property.
Add a QUntypedBindable base class to QBindable<T> that gives access to
generic functionality and checks argument compatibility at runtime.
QBindable<T> will still do static checking at compile time.
Add QMetaProperty::isBindable() and QMetaProperty::bindable()
to be able to dynamically access the binding functionality.
Change-Id: Ic7b08ae2cde83fd43e627d813a886e1de01fa3dc
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>