UIResponderStandardEditActions found in first responder will be prepended to
the edit menu automatically (or e.g made available as buttons on the virtual
keyboard). So we filter them out to avoid duplicates, and let first responder
handle the actions instead. In case of QIOSTextResponder, edit actions will be
converted to key events that ends up triggering the shortcuts of the filtered
menu items.

Change-Id: I046c6cc5b358d8a6f7623e10579e2dcd92f75139
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@theqtcompany.com>