Define an upper bound for RateLimit-Reset

[ioggstream]

I expect

The delta-seconds used for RateLimit-Reset to have an upper bound.

This could help with #15 because we could say that:

• if the value is higher than x it could be processed as an UNIX Timestamp.

Notes

Could 2 days be enough? (eg. 48*3600).

I don't expect issues if I don't respect a 2-day request-quota, though this choice is really arbitrary;