Write a function which accepts an int array and the array size as arguments. The
function should dynamically create a new array which is the same size as the array
passed in. Each element in the new array should be double the corresponding
element in the array passed in. Return a pointer to the new array.
E.g. if you pass in the array \{2, -3, 5\} of size 3, it should create a new array of size 3
with values \{4, -6, 10\} and return a pointer to it.
