Common Lisp path manipulation library

Finally finished(to some extent, at least can’t see anything to add right now) my ppath library - the port of Python’s os.path library to Common Lisp.

The idea of the library is to manipulate pure strings and as file paths as well as to wrap some OS-specific system calls for paths manipulation.

I’ve tested it on LispWorks, CCL and SBCL on Windows, Linux and OSX.