New python service for poller, discovery + more (#8455)

Currently has a file handle leak (and will eventually run out of handles) related to the self update process.

Either need to fix that or rip out self-update and leave that up to cron or something.


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misc/librenms.service

@@ -0,0 +1,14 @@
+[Unit]
+Description=LibreNMS SNMP Poller Service
+After=network.target
+
+[Service]
+ExecStart=/opt/librenms/librenms-service.py -v
+WorkingDirectory=/opt/librenms
+User=librenms
+Group=librenms
+RestartSec=2
+Restart=always
+
+[Install]
+WantedBy=multi-user.target