WVI-35: Add code for lesson synchronisation: service methods for checking and downloading content, servlet methods for communication scenarios, front-end stuff for regular sync checking and displaying information nicely. Made horizon project not expose its beans to global App Context, as it is not needed any more. Add some file utility methods.
WVI-33, WVI-34: Add Learner progress synchronisation code for manual triggering. Fix a bug in prefix-less user creation via IntegrationService. General clean up.