Correct event handlers to trigger in all instnces

Some events don't propagate correctly to the right sub-window
and some things like the pad handler don't even necessarily have
windows. So, just register some events with the top-level app.

Also add a virtual destructor to the PadHandlerBase to be able to
deal with multiple inheritance in the derived classes.

rpcs3/rpcs3.cpp

@@ -82,4 +82,4 @@ CPUThread& GetCPU(const u8 core)
 	return Emu.GetCPU().Get(core);
 }*/
 
-GameInfo CurGameInfo;
+GameInfo CurGameInfo;