Improve number formatting example

Fixes #575

Author: akx

docs/numbers.rst

@@ -18,13 +18,16 @@ Examples:
 
 .. code-block:: pycon
 
+    # Numbers with decimal places
     >>> format_decimal(1.2345, locale='en_US')
     u'1.234'
     >>> format_decimal(1.2345, locale='sv_SE')
     u'1,234'
+    # Integers with thousand grouping
     >>> format_decimal(12345, locale='de_DE')
     u'12.345'
-
+    >>> format_decimal(12345678, locale='de_DE')
+    u'12.345.678'
 
 Pattern Syntax
 ==============