Minor change to dummy_test.

The test now shows how to convert from raw bytes to
a scapy packet.  (Basically just a call to the Ether
constructor.)
Changed "frame" to "state" in stacktrace

The word "frame" was a little misleading in our stacktraces,
so it has been changed to display "state" instead.

Also added comments about some future work for the stacktrace
elements displayed.