Support multiple IPs for agent to ping, use 0s instead of nulls for speedtest

Change-Id: I68290906d808f652b324bccc44f6935ea662b7e2
diff --git a/edge-monitoring/agent_modem/config.json b/edge-monitoring/agent_modem/config.json
index 00bb652..efd0139 100644
--- a/edge-monitoring/agent_modem/config.json
+++ b/edge-monitoring/agent_modem/config.json
@@ -5,7 +5,10 @@
         "baud": 115200,
         "ip_addr": "192.168.0.1"
     },
-    "ping_to": "1.1.1.1",
+    "ips": {
+      "user_plane_ping_test": "8.8.8.8",
+      "speedtest_ping_dns": "8.8.8.8"
+    },
     "report_url": "https://monitoring.aetherproject.org/edges",
     "report_interval": 180,
     "log_file": "/var/log/edge_monitoring_agent.log"