New fields for products in Java api_backend

[yousuowei123]

 */
public FBAFeesObject fbaFees = null;

/**
 * Contains subcategory rank histories. Each key represents the categoryId of the rank with the history in the corresponding value.
 */
public HashMap<Long, int[]> salesRanks = null;

/**
 * The category node id of the main sales rank. -1 if not available.
 */
public long salesRankReference = -1;