Add a recursive merge sort algorithm that accepts an array as input. (#4462)

This is a different recursive implementation of the merge sort algorithm.

* Recursive Merge Sort That Accepts an Array 

Recursive Merge Sort That Accepts an Array

* Add Wikipedia Link

* Fixes naming conventions

* Update sorts/recursive_mergesort_array.py

Co-authored-by: Maxim R. <49735721+mrmaxguns@users.noreply.github.com>

* Update sorts/recursive_mergesort_array.py

Co-authored-by: Maxim R. <49735721+mrmaxguns@users.noreply.github.com>

* Update sorts/recursive_mergesort_array.py

Co-authored-by: Maxim R. <49735721+mrmaxguns@users.noreply.github.com>

* Update sorts/recursive_mergesort_array.py

Co-authored-by: Maxim R. <49735721+mrmaxguns@users.noreply.github.com>

* Update sorts/recursive_mergesort_array.py

Co-authored-by: Maxim R. <49735721+mrmaxguns@users.noreply.github.com>

* Adds black format

* Removes unused variables

* Fixes variable names and adds documentation

* Fixes variable names to use snake_case.

* Removes double #.

* Update sorts/recursive_mergesort_array.py

Co-authored-by: Maxim R. <49735721+mrmaxguns@users.noreply.github.com>

Co-authored-by: Maxim R. <49735721+mrmaxguns@users.noreply.github.com>
Co-authored-by: Benjamin Fein <benfein78@icloud.com>