addrwatch: new package

Maintainer: Ondrej Caletka / @Oskar456
Compile tested: TurrisOS 3.1 (fork of OpenWRT Chaos Calmer), Trunk (both uClibC and musl)
Run tested: mpc85xx - Turris 1.0 -  TurrisOS - no problems observed
Upstream: https://github.com/fln/addrwatch / @fln

Description:

This is a tool similar to arpwatch. It's main purpose is to monitor network
and log discovered ethernet/ip pairings.

The package has been UCIfied, care has been taken to reload the deamon
every time an interface goes up or down.

Signed-off-by: Ondřej Caletka <ondrej@caletka.cz>

net/addrwatch/files/addrwatch.config

@@ -0,0 +1,12 @@
+
+config addrwatch
+	option disabled '0'
+	list interface 'lan'
+	#list interface 'wan'
+	#option syslog '1'
+	#option verbose '0'
+	#option output '/var/log/addrwatch'
+	#list blacklist '192.168.1.1'
+	#option hashsize '1'
+	#option ratelimit '-1'
+