Persist the snmp manager configuration

This commit persist the manager configuration D-Bus objects
and restores it once service starts.

This commit also deletes the associated persistent file whenever
snmp client D-Bus object gets deleted.

Change-Id: I1526b52870ee5dfea30e6527bad3fd12d1191a13
Signed-off-by: Ratan Gupta <ratagupt@in.ibm.com>
diff --git a/snmp_notification.cpp b/snmp_notification.cpp
index b0df691..5f2aea9 100644
--- a/snmp_notification.cpp
+++ b/snmp_notification.cpp
@@ -134,9 +134,9 @@
             log<level::ERR>("Failed to send the snmp trap.");
             elog<InternalFailure>();
         }
-    }
 
-    log<level::DEBUG>("Sent SNMP Trap");
+        log<level::DEBUG>("Sent SNMP Trap", entry("MGR=%s", mgr.c_str()));
+    }
 }
 
 } // namespace snmp