Code by Ladyada to serve web files including multiple levels of subdirectory.
Default is fixed IP address specified by user but can change to a router-served DHCP address.
The new code behaves better but does not implement a true recursive clickable directory tree. See the ls capability in the SD library which does iterate over all files because this will not recurse to further depth than one. Cleaver coders who wish to fiddle with this are welcome to get the code and submit a request with your edits.
