Qt::Key_Clear needs more documentation

In the Qt::Key enum in qnamespace.h, the keypad key labelled 5 is mapped to Qt::Key_Clear (when NumLock is off); it's not immediately obvious that Key_Clear has anything to do with the keypad, I think this should be mentioned in the documentation; something like this:

The key labelled "5" on the keypad (when NumLock is off)