nft-qos: add new package

This is the nftables implementation for qos on OpenWrt,
Currently, it has below features:

* Static QoS : setting limit rate for devices or global network.

* Dynamic/Auto QoS : setting limit rate according to the network
  bandwidth and adjust itself automatically (hotplug event).

* Traffic Priority : this feature is like traffic shaping under tc,
  it uses ingress hook to handle to packets here.

Signed-off-by: Rosy Song <rosysong@rosinson.com>

net/nft-qos/files/nft-qos.init

@@ -0,0 +1,41 @@
+#!/bin/sh /etc/rc.common
+#
+# Copyright (C) 2018 rosysong@rosinson.com
+#
+
+. /lib/nft-qos/core.sh
+. /lib/nft-qos/monitor.sh
+. /lib/nft-qos/dynamic.sh
+. /lib/nft-qos/static.sh
+. /lib/nft-qos/priority.sh
+
+START=99
+USE_PROCD=1
+
+service_triggers() {
+	procd_add_reload_trigger nft-qos
+}
+
+start_service() {
+	config_load nft-qos
+
+	qosdef_init_env
+	qosdef_flush_static
+	qosdef_flush_dynamic
+	qosdef_remove_priority
+
+	qosdef_init_header
+	qosdef_init_monitor
+	qosdef_init_dynamic
+	qosdef_init_static
+	qosdef_init_priority
+	qosdef_init_done
+	qosdef_start
+}
+
+stop_service() {
+	qosdef_flush_dynamic
+	qosdef_flush_static
+	qosdef_remove_priority
+	qosdef_clean_cache
+}