Added solution for exerise 15
Added an async demo
added Futures and Timer excerices
(cherry picked from commit dfdce02)
added Futures and Timer excerices
(cherry picked from commit dfdce02)
Added an async demo
Restored JMS example from previous commit
Merge branch 'master' of https://github.com/kvanrobbroeck/acaddemict-managed into arne

Conflicts:
	ticket-jar/src/main/java/be/ticket/jms/TicketPrinterMDB.java resolved