[Nickle]Array comprehension changes

[Keith Packard]

Carl came up with the improved syntax which now works:

	a)	int[10] i = { [j] = j + 1 };
	b)	int[10] i = { [j] { 
				int c = 0;
				for (int k = 0; k <= j; k++) 
					c += k;
				return c;
			} };

Bart asked for a way to name the array inside the comprehension, so I came 
up with '[]':

		int[10] i = { [j] = dim([]) - j };

-keith