add README, replace Github links

services/nezha-dashboard

@@ -0,0 +1,18 @@
+#!/sbin/openrc-run
+supervisor=supervise-daemon
+name=nezha-dashboard
+output_log=/var/log/${name}.log
+error_log=/var/log/${name}.err
+pidfile="/run/${RC_SVCNAME}.pid"
+command="/opt/nezha/dashboard/app"
+command_args=""
+command_background=true
+directory="/opt/nezha/dashboard"
+
+depend() {
+	  need net
+}
+
+start_pre() {
+    checkpath -f -m 0644 -o root:root "/var/log/${name}.log"
+}