readsb: new package

This package is based on dump1090-fa with many modifications. A big
advantage over dump1090-fa is that it can connect to multiple services
like adsbexchange, piaware or fr24feed.

As the idea for this package is mostly to feed other services, the HTML
files to serve via a webserver have not been included. The service(s)
that will be fed by readsb can offer such a webpage instead.

Finally, the init script does not use local variables, as local is
undefined in POSIX.

Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>

utils/readsb/files/readsb.config

@@ -0,0 +1,46 @@
+config readsb main
+	option enabled '0'
+	option beast_crc_off '0'
+	option beast_df045_on '0'
+	option beast_df1117_on '0'
+	option beast_fec_off '0'
+	option beast_mlat_off '0'
+	option beast_modeac '0'
+	option beast_serial ''
+	option dcfilter '0'
+	option debug ''
+	option device ''
+	option device_type ''
+	option enable_agc '0'
+	option enable_biastee '0'
+	option fix '1'
+	option freq ''
+	option forward_mlat '0'
+	option gain ''
+	option gnss '0'
+	option json_location_accuracy ''
+	option lat ''
+	option lon ''
+	option max_range ''
+	option metric '0'
+	option mlat '0'
+	option modeac '0'
+	option net '1'
+	option net_beast_reduce_interval ''
+	option net_beast_reduce_out_port ''
+	option net_bi_port ''
+	option net_bind_address ''
+	option net_bo_port ''
+	option net_buffer ''
+	list net_connector ''
+	option net_only '0'
+	option net_verbatim '0'
+	option no_crc_check '0'
+	option no_modeac_auto '0'
+	option onlyaddr '0'
+	option ppm ''
+	option stats '0'
+	option stats_every ''
+	option stats_range '0'
+	option write_json ''
+	option write_json_every ''