Formerly, you could only do date offsets in days. You can now do them in days, months, weeks, and years, and they no longer mess up when going over a month or year boundary (thanks to Mark Adler from Nokia for sending me a patch, which I proceeded to distort out of recognizability to add the week/month/year offsets).
Updated the docs so we all know what works now.
Somehow managed to badly hash up the Changelog; now fixed.
I spelled Mark's name wrong (d'oh!).
There was a bug in _zyprexa() for dates rolling forward over a month boundary. Fixed.
