[Etoys] simplifying basic category

Hi,

The current slots/commands in basic category is part turtle geometry and part cartesian geometry. I recast the viewer to include only turtle geometry primitives in basic to make etoys easier for children who are yet to develop intuitive understanding of co-ordinates. Why present two systems when one is sufficient?

I would have liked to make "pen down false/true" to "pen down/up" but I am yet to figure out a simple way to get Boolean slots to support arbitrary strings/symbols instead of just true/false values.

throwing it open for discussions, Subbu