Added some class properties with setters and getters

I’ve created another class named ‘Car’ then I’ve given it some
properties along with accessor methods which allow me to change their
values and fetch them from the class.

I’ve also learned of a case where it’s necessary to initialise an
object, and I’ve learned how to initialise an object. I’m not entirely
sure that I understand how the class name would need to be the type of
my instance variable.

One more thing — I’ve moved my main windows’ starting position to be a
little further up.