Properly deal with classes destructors

There are some classes such as AuditLog that demands a reference count. That is
needed because this class can be used by different instances of the Rules
classes.

src/audit_log_writer_parallel.h

@@ -31,10 +31,22 @@ class AuditLogWriterParallel : public AuditLogWriter {
     explicit AuditLogWriterParallel(AuditLog *audit)
         : AuditLogWriter(audit) { }
 
+    ~AuditLogWriterParallel() { }
     bool init() override;
-    bool close() override;
     bool write(Assay *assay, int parts) override;
 
+    void refCountIncrease() override {
+        m_refereceCount++;
+    }
+
+
+    void refCountDecreaseAndCheck() override {
+        m_refereceCount--;
+        if (m_refereceCount == 0) {
+            delete this;
+        }
+    }
+
     /**
      *
      * Audit log file is saved into a directory structure. This directory