Added pointers to beginning and end of collection

include/json_entities/json_entities.h

@@ -60,7 +60,8 @@ typedef enum {
 struct json_collection {
   u64 size;
   jcoll_type type;
-  jentity_t *first_child;
+  jentity_t *begin;
+  jentity_t *end;
 };
 
 #endif // !JSON_ENTITIES_H