Challenge SmileyFace

Create a SmileyFace object

We have a lovely function for drawing smiley faces, based on object literals
that we pass to it. However, we'd like to use object oriented design instead,
so that we can create instances and add methods. Start off by creating a
SmileyFace constructor that stores centerX and centerY properties.

Var SmileyFace = function(----, ----) {