now what can we do...

the two statement methods are very similar...

there is common structure there but the contents
of the string differes in each one.

This is a candidate for a

  Template Method
  Strategy

First the template method... we create a parent
class for the statement to contain the skeleton
of the algorithm.

We subclass this for the text statement
                         html statement

   in the subclasses we flesh out the abstract methods of
   the parent differently.


First... we create the statement strategy...
need objects for this

also need to add an accessor getRentals to Customer.