aggbuiltin test broken

[Rick Hillegas]

I just sync'd with the trunk and am now seeing pages of diffs in the 
aggbuiltin test. The diffs look like this:

2731 del
< ij> select min(timestamp('1999-06-06 12:30:30')) from t group by ts;
2731a2714
> ij> select min(timestamp('xxxxxxFILTERED-TIMESTAMPxxxxx)) from t 
group by ts;

-Rick