Added adsbexchange-maint.sh.
Added adsbexchange-maint.sh.

jprochazka/adsb-receiver,jprochazka/adsb-feeder,jprochazka/adsb-feeder,jprochazka/adsb-receiver,jprochazka/adsb-receiver,jprochazka/adsb-receiver,jprochazka/adsb-feeder,jprochazka/adsb-receiver,jprochazka/adsb-feeder,jprochazka/adsb-feeder