[10203] Rename item_template.Faction to Flags2 and define some values for it.

Thanks to Shauren for research flag ITEM_FLAGS2_COST_REQUIRES_GOLD meaning
and inspiring in general what must be done long time ago with field rename
and other enum values listing.

src/game/ItemHandler.cpp

@@ -316,7 +316,7 @@ void WorldSession::HandleItemQuerySingleOpcode( WorldPacket & recv_data )
         data << pProto->DisplayInfoID;
         data << pProto->Quality;
         data << pProto->Flags;
-        data << pProto->Faction;                            // 3.2 faction?
+        data << pProto->Flags2;                             // new in 3.2
         data << pProto->BuyPrice;
         data << pProto->SellPrice;
         data << pProto->InventoryType;