Added a method to ungetchar NIL.
Added a method to ungetchar NIL.

GitoriousLispBackup/com-informatimago,informatimago/lisp,informatimago/lisp,informatimago/lisp,informatimago/lisp,informatimago/lisp,informatimago/lisp,GitoriousLispBackup/com-informatimago,GitoriousLispBackup/com-informatimago,GitoriousLispBackup/com-informatimago,GitoriousLispBackup/com-informatimago,informatimago/lisp,GitoriousLispBackup/com-informatimago