## HeaderDoc Class Hierarchy

    HeaderElement                              (Root Class)
            |
            |
            |-----------APIOwner               (Object that owns declared API)
            |               |
            |               |-------Header     (Owner for header-wide API)
            |               |
            |               |-------CPPClass   (Owner for C++ class API)
            |
            |-----------Constant
            |
            |-----------Enum
            |
            |-----------Function
            |
            |-----------MinorAPIElement        (parameter, members of structs)
            |
            |-----------PDefine
            |
            |-----------Struct
            |                |
            |                |-------Var
            |
            |-----------Typedef

    DocReference      (Another root class. Used by gatherHeaderDoc to store information about
                       documentation framesets within an input folder. The script uses this
                       information to construct a top-level table of contents with links to each
                       frameset.)

headerDoc2HTML also uses the non object-oriented module, `Utilities.pm`.