Django commands for certificates

* List of courses that have ended is now a generator
* Using db-aggregation to speed up query for tallies

Removing Askbot

Conflicts:
	lms/envs/aws.py

Fixed redunant rounding of final grade percent, which was causing floating point weirdness.

* Removing the command to find unicode names since it was only used for
  testing
* ungenerated_certs will now by default run through all courses that
  have ended.  a course option can be used to run on one course
* gen_cert_report added which will summarize certificate states
  for all courses that have ended

Add test files to full test course

Feature/brian/press updates

- I added them when playing with input types, but never merged them in

Vik/add self assessment

- also make reset hide the original output

Vik/add self assessment

TODO:
* better css
* green checkmark
* reset button
* tests

Fix syntax on dashboard template

Quickfix to render the dashboard when there is no certificate db tables