Implement Polygon Function

Hi Naomi, 

For this issue, I want you to implement the polygon case in the code we wrote on Friday. This is what the program should look like. 

give the user options for these polygons. (Triangle, quadrilateral, pentagon, Hexagon, Heptagon, Octagon, Nonagon and Decagon). Based on their choice, ask them for the necessary requirement to implement each polygon. 
