Rescale penalties so badly inconsistent messages will tend to get
the same penalty in all formats, so the ambiguity check kicks in.

With this final change the HEADING_SPEED and TRACK_TURN message rates
are almost identical, which is what we'd expect to see if the
interrogator is asking for both at about the same rate.

Before:

    567 AMBIGUOUS
   7445 GICB_CAPS
  19173 EMPTY_RESPONSE
  75252 UNKNOWN
  76469 AIRCRAFT_IDENT
 127603 ACAS_RA
 212654 HEADING_SPEED
 223068 DATALINK_CAPS
 229807 TRACK_TURN
 269267 VERTICAL_INTENT
    466 "suspicious"

After:

   7445 GICB_CAPS
  17432 AMBIGUOUS
  19173 EMPTY_RESPONSE
  75252 UNKNOWN
  76469 AIRCRAFT_IDENT
 127603 ACAS_RA
 212718 HEADING_SPEED
 212878 TRACK_TURN
 223068 DATALINK_CAPS
 269267 VERTICAL_INTENT
    328 "suspicious"