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/modsecurity.cc

@@ -24,6 +24,8 @@
 #include <curl/curl.h>
 #endif
 
+#include "utils/geo_lookup.h"
+
 namespace ModSecurity {
 
 /**
@@ -52,6 +54,10 @@ ModSecurity::ModSecurity()
 
 
 ModSecurity::~ModSecurity() {
+#ifdef MSC_WITH_CURL
+    curl_global_cleanup();
+#endif
+    Utils::GeoLookup::getInstance().cleanUp();
 }