exam: add models
Add post save signals, fix exam properties
add quota start and end dates, find corrector by period, add "submitted" script status
fix various model properties, add migrations
remove box session field
remove Exam object: the script of the exam will be a Document with a type defined in the settings
Display Scripts, fix Script.submit()
Add some Script views and workflow
add Script form, upgrade workflow
style fix
update locale
locales
add corrector courses
Remove Corrector class so that the quotas are directly related to user
fix levels and then auto corrector assignement
fix links and periods
remove period from script form
Add session to Documents
add topics to scripts
fix no topic