Add PyUnicode_DecodeLocaleAndSize() and PyUnicode_DecodeLocale() * PyUnicode_DecodeLocaleAndSize() and PyUnicode_DecodeLocale() decode a string from the current locale encoding * _Py_char2wchar() writes an "error code" in the size argument to indicate if the function failed because of memory allocation failure or because of a decoding error. The function doesn't write the error message directly to stderr. * Fix time.strftime() (if wcsftime() is missing): decode strftime() result from the current locale encoding, not from the filesystem encoding.