Added Exponential Search and Tests

[Calidia]

###32 (Exponential Search)

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• [+ ] Have you created tests for your algorithm?

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Description:

Exponential Search finds the range in which the searched element is instead of searching through the whole sorted array. Once the subset range is found a binary search method is used to determine if the element is within it. The implementation below provides two types of Binary Search - Iterative and Recursive.

[bashbers]

Thank you for contributing!