fixed birthdays in torture.py and added some more thinking.txt
fixed date formatting in patient birthdays

this regularizes the database-side format so the table always contains
%Y-%m-%d formmated dates (with %02d for %m & %d) which makes sorting
on birthday easier (since it's stored as text by sqlite) and searching
more regular (since I can use like '%-$month-%' to find months without
worrying about '09' and '9' being different strings).

ah date semantics I can see why sqlite swept these issues under the
rug. switching to mysql of course would give us the ability to bring
all this hairiness down to the database level. is that a good thing?
more thinking