Extend functions r:eval-exp with support for booleans in racket.

(a) Implement a data structure r:bool (using a struct) with a single field called value that holds a boolean.

(b) Extend the evaluation function to support boolean values.

(c) Extend the evaluation to support binary-operation and. The semantics of and must match Rackets operator and. Recall that Rackets and is not a variable to a function, but a special construct, so its usage differs from function +, for instance.

(d) Extend function + to support multiple-arguments (including zero arguments).

(e) Extend primitive and to support multiple-arguments (including zero arguments).