Various macros for positioning objects.

In the following examples, `S`

is a sphere primitive with
radius 0.5, and `C`

is a cube of length 0.4.

`RotSpace(N, R, Ob)`

:

`N`

copies of object `Ob`

at evenly spaced angles in a circle
of radius `R`

.
`RotSpace_SR(N, R, Ob, Sc, Rt)`

:

`RotSpace(N, R, Ob`

, with the `K`

th copy of `Ob`

scaled by
`1+Sc*K`

and rotated by `Rt*K`

for each `K`

in `0,...,``N`

.
```
```

```
```

`Row(Ob, Start, N, Space)`

:

Constructs a union containing `N`

copies of object `Ob`

in a row, starting at point `Start`

and spaced apart by vector
`Space`

.
Rows may be iterated to produce more complex objects. For example:

`Row_SR(Ob, Start, N, Space, R, S)`

:

Same as ```
Row(Ob, Start, N,
Space)
```

but with the `K`

th copy of `Ob`

scaled by
`1+S*K`

and rotated by `R*K`

for each 0,...,`K`

.