Pathname implementation using Array

Any interest in this reimplementation of Pathname that uses an Array
instead of a String? It's based on the current standard version in
Ruby, I just changed @path from a string to and array and adjusted the
rst of the code as needed. It appears to be about 20% faster. And it
can be made even more flexiable too, I've already added #<< (which is
what I've been wanting) and other methods could be easily added like
#pop, #shift, and even include Enumerable if desired. Also, now that
@path is an Array, it might not hurt to go the next step and make
Pathname a subclass of Array instead, that'd probably make it a tad
bit faster again.

Still, I imagine Pathname should ultimately be coded-up in C,
nontheless using an Array as the core data contatiner instead of a
Sting looks to be a nice improvement.

T.