TODO with etimedate:
* calendar
- review methods and add new, for better future usability
- create new doxygen documentation
- add ability to calculate difference between selected date and today
* clock
- redesign clock - use bitmaps for background and possibly hands
- add seconds to input and buttons
- use Date_Time class
- remove unnecessary methods, add new ones
- merge two boxes?
- make hands movable with mouse
* timezones
- add city coordinates (find in evolution / kde), draw current zone on map
- make map sensitive / hotspots on city coordinates
* Date_Time class
- new class