Make FloatItems store their positions
completed by: Illya Kovalevskyy
mentors: Torsten Rahn, René Küttner, Dennis Nienhüser
Currently the floatitem positions get reset to their default values once Marble gets restarted.
During this task the positions should get stored via the Marble settings infrastructure on quitting/closing Marble. And they should get restored once Marble is started.
A follow-up task will introduce a context menu entry that allows to restore the default position.
The feature should work both for the Qt and KDE version.