OO-2636: only show the useful segments of the lectures administration in a course, if disable only show the configuration, if enable all segments; and update the toolbar aafter configuration changes

OO-2636: database setup, overview list of participants with statistics and custom attendance rate editor

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-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: 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-1859: fix controller disposed if someone in member management of course selects a group and close the group with the red cross

OO-1645: propagate the business rules for private event on home calendar and calendar tool of the course