Cleaned the imports.
Removed db4o since not needed now.
Updated menu button to indicate that a new window will open if the user clicks the button.
Added a ConversationWindow where the chat conversations will happen. The work is not complet.
Added keyboard codes since they are used at several places.
Added contacts to the list and configured what happens if one double clicks on a contact.
Simplified this dialog and added input validation.
Added the conversations window features.
Cleaned the imports.
Removed a mock since it was not needed anymore.