add deposit_history and withdraw_history

Author: you21979

lib/private_api.js

@@ -56,6 +56,8 @@ var createPrivateApi = module.exports = function(api_key, secret_key, user_agent
         getInfo : function(){ return query('get_info', {}) },
         tradeHistory : query_method('trade_history'),
         activeOrders : query_method('active_orders'),
+        depositHistory : query_method('deposit_history'),
+        withdrawHistory : query_method('withdraw_history'),
         trade : function(currency_pair, action, price, amount){
             return query('trade', {
                 currency_pair : currency_pair,