Remove the SelectionMover class and associated code

The removed tests have been superseded by SelectionController tests covering
the same functionality.
Migrate SelectionMover.createPositionIterator to OdtDocument

Remove the SelectionMover file entirely as it no longer contains any
functionality.
Merge pull request #730 from peitschie/selectionmover-cleanup

Remove superseded SelectionMover class
Screen blanking for presentations + additional hotkeys for navigation
Only support blankout in presentation mode

Also:
* no navigation in blankout mode
* leave blankout when presentation mode is left (e.g. by browser on ESC)
Support more API variants to enter/leave fullscreen (with input support)