Implementing banner

[Seyaku]

Before using Json I made this class, to be implemented by each item handler that needs custom metadata.

/** Storage class for item meta data */
class cItemMeta
{
public:
  virtual ~cItemMeta() {}

  /** Load from NBT source. */
  virtual void FromNBT(const cParsedNBT & a_NBT) = 0;

  /** Load from copy. */
  virtual void FromCopy(const cItemMeta * a_Meta) = 0;

  /** From JSON */
  virtual void FromJSON(const Json::Value & a_Value) = 0;

  /** Write to NBT */
  virtual void ToNBT(cFastNBTWriter & a_Writer) = 0;

  /** To JSON */
  virtual void ToJSON(Json::Value & a_OutValue) = 0;

  /** Is equal to */
  virtual bool IsEqual(cItemMeta * a_ItemMeta) = 0;
};