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

OO-2515: save the master file untouched, deliver  more pixels for the print view of the members course element, add REST api methods to check if a particular size of portrait is available

OO-2429: move the foreign key from identity to user, remove double mapping of identity, add more unit tests for invitation, unify the methods to create the user and identity

OO-2354: decouple attribute sued to search a user on the LDAP server from the user identifier and make it configurable, add embbeded LDAP server for unit tests

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

no-jira: fix some unicode characters, better length check in velocity template, add some infos for user properties context

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