Login happens only with authentication informations, identity name is
now only used for legacy directory name. User name of authentication can
be changed. LDAP users can be imported with LDAP::ldapUid. Users can be
imported in courses, groups... with First name last name.

OO-3489, OO-3490, OO-3491, OO-3495, OO-3499, OO-3500, OO-3501: finish the export process, delete files after zipping, send email... and more exported data

OO-3489, OO-3492, OO-3493, OO-3494, OO-3496, OO-3497: infrastructure to export user data, export  portraits, notes, personal folder, calendars, subscriptions, delete calendars after usser deletion

OO-3297, OO-3301: refactor security group management operations in its own DAO, implement isInOrganisation mfunction for course expert rules

OO-3297: refactor the user management to use organization for managing the roles instead of named security groups

no-jira: add unit test for a password checker with at least 8 characters, a number, a special character, a lower and upper case character

OO-2241: remove optimized getter access to user properties, remove stupid unit test, change unit tests with the !keePEmail option

OO-1443: upgrade JUnit ( long overdue ), remove deprecated junit.* packages, fix some issues with order dependent tests, fix an issue with empty ClusterDoInSync

OO-1436: fix an issue with a method's signature, log audit creation of identity and authentication, show errors after import of users...

OO-1068 OO-1113 more bootstrapify of forum, refactor redundant avatar image code, add forum attachment preview