Adds 'n' as a format specifier for integers, to mirror the same
specifier which is already available for floats. 'n' is the same as
'd', but inserts the current locale-specific thousands grouping.
I added this as a stringlib function, but it's only used by str type,
not unicode. This is because of an implementation detail in
unicode.format(), which does its own str->unicode conversion. But the
unicode version will be needed in 3.0, and it may be needed by other
code eventually in 2.6 (maybe decimal?), so I left it as a stringlib
implementation. As long as the unicode version isn't instantiated,
there's no overhead for this.
Highlights:
- Adding PyObject_Format.
- Adding string.Format class.
- Adding __format__ for str, unicode, int, long, float, datetime.
- Adding builtin format.
- Adding ''.format and u''.format.
- str/unicode fixups for formatters.
The files in Objects/stringlib that implement PEP 3101 (stringdefs.h,
unicodedefs.h, formatter.h, string_format.h) are identical in trunk
and py3k. Any changes from here on should be made to trunk, and
changes will propogate to py3k).