Adds new method for rule merge

IMPORTANT: SecDefaultAction specified on a child configuration will
overwrite the ones specified on the parent; Previously it was
concatenating.

src/operators/verify_svnr.h

@@ -34,7 +34,7 @@ class VerifySVNR : public Operator {
 
     bool evaluate(Transaction *transaction, RuleWithActions *rule,
         const std::string& input,
-        std::shared_ptr<RuleMessage> ruleMessage) override;
+        RuleMessage *ruleMessage) override;
 
     bool verify(const char *ssnumber, int len);