#4 Writer doesn't handle Long integers

[Barry Pederson]

In Python 2.3.5, json.py fails when writing long
values. For example:

import json
json.write(12345678901234567890)

results in

-------
WriteException: Cannot write in JSON: 12345678901234567890
-------

I've attached a patch that fixes the problem, and
includes a couple more unittests that check handling of
large values.

[Barry Pederson]

Patch to support long values