Database reconstruction

Upon further examination, the db files needed to do things like in [the python + sql lesson](https://github.com/swcarpentry/sql-novice-survey/blob/gh-pages/10-prog.md) don't seem to be around. What's more, just committing those db files might be a bad idea, based on the versioning problems I pointed out in #11. So, `code/buildDB.py` will generate a database file to be used in that lesson using whatever sqlite machinery the local python prefers.

Also updated some docs to match (and sucked up some changes to `index.html` from a previous commit that forgot to re-`make` the html).