Added currency symbol for RUB

src/calibre/gui2/store/stores/litres_plugin.py

@@ -112,7 +112,7 @@ def format_price_in_RUR(price):
     '''
     if price and re.match(r"^\d*?\.\d*?$", price):
         try:
-            price = u'{:,.2F} руб.'.format(float(price))
+            price = u'{:,.2F} \u20BD'.format(float(price)) # \u20BD => руб.
             price = price.replace(',', ' ').replace('.', ',', 1)
         except:
             pass