Fix a few memory leaks

- Rewrite zonename_array to use std::map rather than a pointer to an array
of character pointers

- Properly delete ZoneConfig on Zone shutdown

- Delete AdventureTemplates in AdventureManager destructor

common/database.h

@@ -255,8 +255,7 @@ protected:
 private:
 	void DBInitVars();
 
-	uint32				max_zonename;
-	char**				zonename_array;
+	std::map<uint32,std::string>	zonename_array;
 
 	Mutex				Mvarcache;
 	uint32				varcache_max;