(Printed Representation): Clarify read syntax vs print.

(Printed Representation): Clarify read syntax vs print.
(Floating Point Type): Explain meaning better.
(Symbol Type): Explain uniqueness better.
(Cons Cell Type): Explain empty list sooner.  CAR and CDR later.
List examples sooner.
(Box Diagrams): New subnode broken out.
Some examples moved from old Lists as Boxes node.
(Dotted Pair Notation): Clarify intro.
(Array Type): Clarify.
(Type Predicates): Add hash-table-p.