Minor updates this week

As well as the new world editor, there have been some other small updates to JAKE this week.

Firstly, the graphics have been improved slightly in the JAKE Java library, so that there's no longer the same stretching and pixelating as before. The wall and beeper icons are now crisper. You can see this in one of the screenshots for the world editor, when compared to a scenario from a few weeks ago:

Secondly, tooltips have been added. The two screenshots below show how tooltips show up in both the world editor and the class diagram. For world editor objects, the tooltip shows the name and type of the object (e.g. "jake (robot)" or "myBeep (beeper)"). For class icons, the tooltip describes this class's relationship to its parent:

Finally, the WorldObject class has been replaced by "Thing". This saves any confusion from having the "World" and "WorldObject" classes next to each other in the diagram; we didn't want it to appear that WorldObject was an instance of World. So, now, all objects in the World are "Things".