new stats update schedule

We have switched the stats (points) update to occur every 3 hours instead of every 2 hours.  The reasoning here is that it takes about an hour to update the stats, and so doing this every 2 hours means that the stats are accessible only 1 out of every 2 hours.  However, doing the stats update every 3 hours doesn't take that much longer to update the stats (1 hour and 15 minutes vs 1 hour) and so this should make the stats more available.  The reason it doesn't take that much longer is that the stats update is done in batches by project to help db thrashing in and out of memory and so once a project db is in memory, it doesn't hurt to push through more stats.

We're going to try out this new schedule to see if this bears out.  If not, we'll go back to the old schedule.