Summarize data

Please, check my code!
I forgot to include some kind of readme.st. To test custom command:
python manage.py summarize [date YYYY-MM-DD] [--nodeletion]
If you pass no parameters it summarizes current date minus 15 days (single day and no a 15-days period)
I think I got this wrong. Usually the Optparser options object allows you attribute access but I forgot that Django does something in between and you can't access it that way.

So, sorry for the confusion.