better ip to int conversion & better tz data

Hi,

I patched the `util.ip2long()` function hoping that `inet_pton` could deal with more obscure IP formats like 

    >>> int(socket.inet_aton('74.125.235.3').encode('hex'), 16)
    1249766147
    >>> int(socket.inet_aton('0x4a.125.60163').encode('hex'), 16)
    1249766147

Also did some timezone.py clearup, hope it's better formatted.