feature #192: free log resources in NebulaLog and base PoolTest class

include/NebulaLog.h

@@ -58,6 +58,11 @@ public:
         }
     };
 
+    static void finalize_log_system()
+    {
+        delete logger;
+    }
+
     static void log(
         const char *            module,
         const Log::MessageType  type,

include/test/PoolTest.h

@@ -362,6 +362,8 @@ public:
         if (!log_flag)
             remove("test.log");
 
+        NebulaLog::finalize_log_system();
+
         return 0;
     }
 };