1.  Given n, write a function that returns
    a list of the first n positive squares 

> allsquares 5
[1,4,9,16,25]

2.  Write a sublist function that returns
    a portion of a list

> sublist 1 3 [1,4,9,6,5]
[1,4,9]
> sublist 3 6 [1,4,9,6,5,2]
[9,6,5,2]

3.  Write a merge function to support mergesort

> merge [1,3,5] [2,6,7,8]
[1,2,3,5,6,7,8]

4.  Write a mergesort function

> mergesort [1,4,9,6,5]
[1,4,5,6,9]