chore: update systemd readme

README.md

@@ -8,4 +8,21 @@
 * Service
     * https://bitbucket.org/hatterjiang/linux-service-sample/src/master/
     * https://stackoverflow.com/questions/61443052/rust-daemon-best-practices
+    * https://wiki.archlinux.org/index.php/systemd
 
+
+Sample of aliyun service:
+```shell
+# cat /etc/systemd/system/aliyun.service 
+[Unit]
+Description=aliyun-assist
+After=network-online.target
+[Service]
+Type=simple
+ExecStart=/usr/sbin/aliyun-service
+KillMode=process
+Restart=on-failure
+RestartSec=1min
+[Install]
+WantedBy=multi-user.target
+```