This example demonstrates the creation and rendering of a sphere using
indexed geometry and vertex arrays.  While more complex to initialize than
glBegin/glEnd immediate mode geometry, vertex arrays require less code to 
render each frame, and can perform much better.  Also, they allow vertex 
indexing for shared vertices.  This demo actually has fewer visual features
than the previous demo - but it will form the basis for the later demos in 
this chapter, and is mainly of interest for its code

The key commands are:

i, k - translate in x
j, l - translate in y
u, o - rotate around z axis
p, ; - uniformly scale
Space - reset transforms
