Allow @SuppressWarnings Checkstyle module
Add @PreferenceScreen
Implement PreferenceScreenHandler
Add @PreferenceByKey
Implement PreferenceByKeyHandler
Add @PreferenceChange
Refactor AbstractListenerHandler

So now it can be used for other types of listeners then View listeners.
For View listeners, a new subclass, AbstractViewListenerHandler is
created.
Implement PreferenceChangeHandler
Add @PreferenceClick
Implement PreferenceClickHandler
Add @AfterPreferences
Implement AfterPreferencesHandler
Add @PreferenceHeaders
Implement PreferenceHeadersHandler
Allow more then 100 methods in ValitorHelper with Checkstyle
Add JavaDoc for new @PreferenceXXX annotations
Add tests for @PreferenceXXX annotations