Add QObject::objectNameChanged(const QString &objectName) signal

Add QObject::objectNameChanged(const QString &objectName) signal

This is sent when the object's name changes.

tst_moc must be updated since the method count of QObject has changed.
The test assumed that there were 4 invokable methods in QObject. The
new signal is the 5th, which breaks the test's assumptions. Fix this
as well.

tst_QObject must be updated since the
QObjectPrivate::isSignalConnected() method only supports the first 64
signals. With the addition of this new signal, sig61() in the test
becomes the 65th signal, and will always appear connected now.

Task-number: QTBUG-13999 (related)
Change-Id: Ie87893c71a231fafa7ccf2f16102238a7be8327a
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>