Area Under a Curve Algorithm (#1701)

* A recursive insertion sort

* added doctests and typehints

* Added arc length and numerical integration calculators

* fixed doc test

* Fixed some conversion errors

* Fixed some commenting

* Deleted numerical integration to allow 1 file per push

* Changed string formatting method

* Added program to calculate trapezoidal area under curve

* Deleted files ensure 1 pull request per file

* file name changed

* Update area_under_curve.py

Co-authored-by: Christian Clauss <[email protected]>