figure out how to accommodate sqlite db changes

[ckolderup]

Since it's been just me using this software up until now, it's not a huge deal if I break things when I pull down new code-- I can figure out what happened and change the sqlite schema to match whatever changed in the DB setup code. But with other people installing the app and theoretically wanting to pull in new changes, I'm going to need to restructure the way that DB stuff is initialized so that it can figure out if anything's out of sync and update appropriately.