SumSection
* Given an integer array nums, and a starting and ending index,
return the sum of the numbers from the
starting to the ending index. If either index is out of range, correct it.
A bad beginning index should get the first index.
A bad ending index should get the last index.
*
SumSection([1, 2, 3, 4, 5], 1, 2) - 5
* sumSection([2, 4, 6, 8, 10, 12, 14), 0, 4) - 30
sumSection([5, 10, 15), -1, 1) 15
I
*/
public static int sumSection(int[] nums, int start, int end)