add a bsd rc dist

dist/kcptun.dist

@@ -0,0 +1,20 @@
+#!/bin/sh
+# FreeBSD startup script, rename and put this file to 
+#   /usr/local/etc/rc.d/kcptun
+# and, run:
+#   chmod +x /usr/local/etc/rc.d/kcptun
+#   echo kcptun_enable="YES" >> /etc/rc.conf
+#   service start kcptun
+
+. /etc/rc.subr
+
+name="kcptun" # How the service will be invoked from service
+rcvar="${name}_enable" # The variable in rc.conf that will allow this service to run
+load_rc_config $name # Loads the config file, if relevant.
+
+dir="/home/xtaci"   # change this to the directory where kcptun binaries are.
+pidfile="$dir/kcptun.pid"
+start_cmd="daemon -p $pidfile $dir/client_freebsd_amd64 -c $dir/local-ss.json"
+stop_cmd="kill $(cat $pidfile); echo kcptun is not running."
+
+run_rc_command "$1"