Filter agent in reservations

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>
Workaround for stats with lots of reservations

sqlite raises "too many sql values" in prefetch_related()
and in filter(key__in=[...])

Do not calculate persons and receipts for reservation > 900.
TODO: switch to postgres.

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>
First implementation for logging to files

Save resevations to cvs format files with +++ separator.

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>
Some templeate and css changes

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>
Some more style changes

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>
Support cvs, log, and html output

Signed-off-by: Dimitris Aragiorgis <dimara@grnet.gr>