OO-1604: fix the red screen, fix the stupid warning, wording for the editors, create the tasklist object by import and copy of courses

OO-1599: fix a red screen if the task assignment step is enabled after someone started the process without it, add a confirm in the editor

OO-1583: if a step is disable, check that the task is not in this status and if it's the case, push the task to the next step

OO-991 i18n, xss, fix filename in download, add mail form for coach, improved status feedback, allow submission without documents, add missing identity to created files

no-jira: make the group task coure element for owner only, fix RS if there isn't any "next step", french wording, remove visit entirely, add member icon (Font Awesome 4.3)...

OO-1562,OO-1563: add a member management right to the list of course rights and restricts the access to the function of the course members management in function of the administration/group/member rights