First part of new readable test for refactored ListenerManager.
Added ListChangeListener and InvalidationListener support to ListenerManager
Merge branch 'develop' into listener-manager

# By Manuel Mauky (3) and others
# Via Alexander Casall (3) and Manuel Mauky (3)
* develop:
  Ignore IntelliJ IDEA project files in git repository
  added missing licence header for ModuleFactory
  reduced visibility of some internal classes. created an inline guice-module factory so that there are no module-classes are needed anymore
  Added clearSelection functionality to SelectableItemList
  - renamed some tests to make clear that the itemList is changed
  - ItemList supports real synchronization: instead of deleting all elements in the target collection, all updates are propagated and executed on the target list
register Invalidationlistener - added put to map after registration
Deleted Listener Cleaner
small copyright
Merge pull request #37 from sialcasa/listener-manager

Review is done, everything is ok.