Read in a .class file and parse and register the class for use by Axe.
:dir ; default nil
class-file — (required)
A path to a .class file, relative to the directory indicated by the dir argument.
:dir — default nil
Either nil, in which case the class-file is interpreted relative to the cbd, or a keyword indicating a directory registered with add-include-book-dir or add-include-book-dir!.