Current fix for most issues

* Fix for support multiple workers of same type
* Extract responsibilities of WorkerRegistration to Scheduler and new Initializer class
* new Listener class (when job is submitted)

* updated fairshare to use new listener and responsibilities
* updated Queue findTask method so no wrong tasks can be fetched
* Queue leaseTask synchronized for multiple thread access

Remark!!!:
To be able to run the examples they will need to be updated. New ServletContextListener!!!