Created attendance model.
Starting to wire sinatra app to old csv based report generator.

The old report templates worked pretty well, so I'm hoping to wire up
the db to the same variables in the report class. This commit is
part-way through stage 1; putting in dummy values for the variables and
getting it to spit out a report without errors.
All variables for the report cards are being pulled from the db.

TODO: the web interface needs a place for attendance data to go in.
automated creation of all html reports
added facility for logging in for attendance
made more portable, enhanced grade input
template cleanup
fixed crashing typo
removed incorrect table heading in level 78 language arts outcomes
enhancements to the admin interface

Fixed the home tab on the navigation to go to the admin's home when
logged in as admin. Added a clear reminder to set the current working
quarter.
added label to date field in grading period input interface
changed the structure of the outcome set to embed multiple comment objects
removed comment field, restored subject relation
added the comment editing history and separated the grading from the comments
removed all trailing whitespace
Merge branch 'editing-comments'
tidy up