Handles better the memory utilization

- Added reference counts to Rule and AuditLog;
- Some memory leaks were removed, including GeoLookup;
- Deal better with parser errors;
- Overriding the AutlogLogWritter destructor.

src/audit_log_writer_serial.h

@@ -37,7 +37,7 @@ class AuditLogWriterSerial : public AuditLogWriter {
     explicit AuditLogWriterSerial(AuditLog *audit)
         : AuditLogWriter(audit) { }
 
-    ~AuditLogWriterSerial();
+    ~AuditLogWriterSerial() override;
 
     void refCountIncrease() override {
         m_refereceCount++;