Input popup updates:
- SimpleLinePopup is now based on EmbeddedSingleLine
- New ListPopup class: selection from a list
- New ListPopupModel interface for ListPopup
- New FixedListPopupModel class: ListPopupImplementation for fixed list
Registry:
- Registry app gets ValuesArea for values preview and edit
- Registry implementation gets proper function to obtain list of values in particular directory
Registry:
- Directory insertion implemented

Environment:
- Luwrain.popup() method added
Registry:
- Value insertion implemented
- COrresponding code for registry implementation (setString, setInteger, setBoolean) added
Minor changes:
- YesNoPopup added
- Confirmation on exit added
- Fixed bug with type cast in ScreenContentManager on activating next are