Refactor UAT implementation for ADSB Exchange and clones

[ketilmo]

From @wiedehopf, via Discord:

https://github.com/ketilmo/balena-ads-b/blob/master/adsb-exchange/start.sh
your UAT logic is only sending to adsbexchange and not to clones (somewhat unfortunate term) unless i'm missing something.
you can just add a net connector to readsb (named feed-adsbx in this case):
--net-connector dump978,30978,uat_in

And then remove the special handling for adsbexchange and remove the 978 convert script, it's not been necessary for some time.

Considering this PR: #190, you could just use ultrafeeder to send data to all those sites including adsbexchange though (docker-tar1090 / ultrafeeder containers are basically the same, might as well go all the way and add the interface with the feeding that has the MLAT results from all sites nicely bundled up)

[shawaj]

nice...I think we would just need to detect if uat is enabled higher up in the start script and then add the info for uat to the feeder

[shawaj]

Could do #167 at same time potentially

[wiedehopf]

The functionality of feeding adsbexchange and the other sites is integrated with ultrafeeder.
Which is really the same size as just docker-tar1090.

So yeah best to just add ultrafeeder and use it to feed 978 / 1090 / MLAT to the sites.
ultrafeeder will have a separate readsb running (mlathub) which aggregates mlat results.
You can push them into dump1090-fa easily for display there.
They'll be also displayed in the tar1090 webinterface of ultrafeeder.

Should be very possible to just produce a yml to run ultrafeeder from the config.
But that's up to you.

Having --net-connector dump978,30978,uat_in added to the commandline before feed-adsbx (readsb) is started will do the job.
Though i suppose you want to use your env vars.

[wiedehopf]

If you ignore the RTLSDR part, this is good example for an ultrafeeder yml: https://sdr-enthusiasts.gitbook.io/ads-b/foundations/deploy-ultrafeeder-container