Add saving notifier to attendance.
Move mda-client egg to db-interface import.
Add dev* scripts.
Rename list-index to list-index-prefix to prevent an import overwrite.
Use null? instead of length.

For performance, correctness.
Refactor macs to module. Add make-global-parameter.
Clean up some parameters.
Add db setup interface.
Use new macs instead of old one.
Fix bug that was causing the wrong value to be returned.
Add db-interface tests.
Add macs tests.
Add etc/database.scm to keep-the-records.scm includes list.
Add constants exports.
Add pause/resume.
Have remaining db procedures use with-db.
New mutex setup for pausing.
Threaded db tests.
Update copyright/license.
Pull mutex utils into a separate module.