[schooltool] new SchoolTool sample data

[Tom Hoffman]

I've updated the SchoolTool book to reflect the new sample data
import, so if you want to see your school with some fake students and
classes, read this:

http://book.schooltool.org/htmlhelp/sample.html

This implementation is rough around the edges (as described in the
documenation), but it should work. Ignas has been smoothing out the
edges this week.

--Tom