OO-1808: show a message if the course element cannot deliver a view after an author published the course

OO-1616: fix the certificate unit test in the REST API suite, don't doInSync during import of the course, remove get resource method (duplicate), remove unused constructor and method

no-jira: add selenium test for the direct deletion of user, remove empty info in the panel to create a business group, add the missing parameter of the uploaded by i18n key in different languages

OO-1799: don't remove the reference of Test, Survey, Selt-test, CP and SCORM during the copy of a course element within the course

OO-1783: add a warning message if the coach hasn't any document send for corrections/revisions, wording

OO-1616: update user course infos via SQL statement, don't retrieve identity with the bookmark in course

OO-1785: revert order of first name and last name, make not mandatory property visible but not by default

OO-1786	: show the subscription on the list of groups/participants, clearfix the subscription in the individual/group view, wording

OO-1761: more fix to the copy of course element within a course, copy or import of a course with a project broker element

OO-1770, OO-1769: allow pseudonym and guest posts, refactor the message model to hold only threads or messages of a unique thread in memory, minimize the number of joins on query, minimize the number of queries on peekview, remove buggy docking feature...