Binary Search Bug Fix and Update for Testing

[normand1]

Problem

When searching for a key within a non-complete array (e.g. [0,4,7,9,13,16,34] as opposed to [0,1,2,3,4,5,6,7]) the binarySearch() function returns an initial correct print statement followed by a false positive.

Run:

sorting.binarySearch([0,4,7,9,13,16,34], key: 8)

Result:

   search value 8 not found..
   search value 8 found..

Solution implemented this PR

• Updated binarySearch(_:) to be testable (now returns true or false depending on whether the key was found in the sequence)
• Updated the test to test all possible values of a given array

[waynewbishop]

Hi David, thanks for your interest in the book and for submitting this pull request! So that I can review your work in detail, if you could set the target branch of your PR to point to develop that would be great.

[normand1]

Hi @waynewbishop great book, thanks for writing it. I'll update my PR now.