Added the NEWS file.
Renamed NOTES.txt to NOTES.
Added the raja.util.FileHelper class: helper class for file operations.
Updated UI with the new Scene achitecture.
Minor cosmetic changes.
Added class World which Replaces the old Scene class. A Scene is now a
Added a NOTES.txt file to keep track of some implementation choices.
Updated raja.ui classes to use Raja's new Image I/O classes.