Time of exactly 30 days is treated as timestamp, not timedelta

[Quanyails]

According to the Memcached wiki, expiration times in the range [0, 60*60*24*30] are treated as timedeltas, while anything higher is treated as a timestamp. The value 60*60*24*30 == 2592000 is currently treated as a timestamp when it should be a timedelta here.

Example:

import mockcache
mc_client = mockcache.Client()
mc_client.set('key', 'value', 60 * 60 * 24 * 30)
assert mc_client.get('key') is not None  # currently returns None