Added logical-pathname parser extracted from COM.INFORMATIMAGO.COMMON-LISP.VIRTUAL-FILE-SYSTEM.
Added logical-pathname parser extracted from COM.INFORMATIMAGO.COMMON-LISP.VIRTUAL-FILE-SYSTEM.

informatimago/lisp,informatimago/lisp,informatimago/lisp,informatimago/lisp,informatimago/lisp,informatimago/lisp,informatimago/lisp