Rename model package to bean
ContactController use new ContactModel
Move createContact() to Utils
Fix Conferences display in Contacts
Reorganize and beautify Code
Added MucListener

Conflicts:
	src/main/java/de/xsrc/palaver/utils/Utils.java
Moved connection logic to tasks
Move Bookmark Sync to ConnectTask
F:CRUD on account reconnects connections
Use Tasks and Executors

- At the moment for convinience is the ObservableTaskExecutor used, not
  sure if it's a good performance sollution
Fixed Conference Bookmarks