OO-2531: implement print and download raw dat for QTI 2.1 in statistics views, refine list of users seen by admin, authors, coaches in statistics (courses and resources) and in asessment tool

OO-2442: implement an upgrader to set the status to inProgress for some old task course element entries, set the status if someone take a task or upload a file

OO-2430: update paypal libraries, fix configuration trailing tab, fix return from paypal, fix transaction sort by date and status in administration, fix missing icon...

OO-2043: add message under the toolbar is a course is freezed, better handler changes of status, reload course element by status changes...

OO-2371: check if the participant is in group of a enrollment element before allowing it to leave the course

OO-2172: refactor the spring configuration to be more Spring 4 friendly, remove the cycle generate by the properties injection, deployment of course and user in a separate module

OO-1593: rework the interaction behavior of the access rights controller for invitation, fix search invitation per identity, fix rs in invitee mode

OO-1593: implements several strategies for the state "failed", implements done in assessment tool, checklist and group task...

OO-1593: implementation reset of users data in QTI 2.1 course element and resource, add statistics for resource...

OO-1593: fix diverse issues in assessment tool and QTI 2.1, wording, selenium tests use the new assessment tool

OO-2132: dispose controller which own a sub tree in course tree if clicked on their root node, don't persist the mapper for CP, fix gremlin in iframe.js