wevents.icn: Program to report Icon window events

   wevents reports all the events delivered to an Icon window.
Each event produces a single line of output.  The program terminates
after receiving and reporting a ^C, ^D, or DELETE key event.

   Each event is reported both in Icon terms and in terms of its
internal representation.  The output fields on each line are:

     &interval (interval since previous event, in milliseconds)
     &control, &meta, &shift (modifier keys: c, m, or s if pressed)
     event returned by Event: keyword name, if any, or else image
     &x, &y (usually coordinates, but new size for resize event)

     image() of the first value on the event queue
     hex dump of the second value (modifier flags and x coordinate)
     hex dump of the third value (encoded interval and y coordinate)