Fix currency type for bitcoinvenezuela history

update exchange rate history for bitcoinvenezuela exchange

plugins/exchange_rate.py

@@ -506,7 +506,7 @@ class Plugin(BasePlugin):
                 tx_time_str = datetime.datetime.fromtimestamp(tx_time).strftime('%Y-%m-%d')
                 try:
                     num = self.resp_hist[tx_time_str].replace(',','')
-                    tx_fiat_val = "%.2f %s" % (Decimal(str(tx_info['value'])) / 100000000 * Decimal(num), cur_currency)
+                    tx_fiat_val = "%.2f %s" % (Decimal(str(tx_info['value'])) / 100000000 * Decimal(num), self.fiat_unit())
                 except KeyError:
                     tx_fiat_val = _("No data")