Change KEYBOARD-READ, KEYBOARD-PEEK, and KEYBOARD-PEEK-NO-HANG to

Change KEYBOARD-READ, KEYBOARD-PEEK, and KEYBOARD-PEEK-NO-HANG to
intercept "update" and "resize" events and to handle them rather than
returning them.  Other events with potentially troublesome actions are
returned as before.  Additionally, several places where input events
were discarded have been fixed -- input events must ALWAYS be handled.