Feature: STATISTICS for messages received per frequency

[Minglarn]

Hi! So much in love with this ACARS HUB project.
On thing I miss is to know witch frequency is most active.
The statistics page is briliant, but would be even more nice to have if you could sort out witch frequencies are used most.

Why? It could be nice to se the "dead" frequencies out so the decoders with "dead" time could be sorted out.