Write the function insertion_sort(a) that takes an array of numbers and returns an array of the same values in nondecreasing order, without modifying a. Your function should use the insert function written in the previous problem.

>> b = Array.new(12) {Random.rand(100)}

=> [30, 81, 43, 95, 24, 38, 64, 56, 74, 70, 33, 60]

>> insertion_sort(b)

=> [24, 30, 33, 38, 43, 56, 60, 64, 70, 74, 81, 95]

>> b

=> [30, 81, 43, 95, 24, 38, 64, 56, 74, 70, 33, 60]

>> insertion_sort(b) == b.sort

=> true