Added ability to add, edit, and delete virtual directories to/from applications

This adds the ability to add, edit, and delete virtual directories to and from applications.  This is a valuable tool of iis as it allows share/static resources to be attached to one or multiple web applications.

This works with local and UNC paths, including samba shared directories.

If you have any questions please ask, this is something that our company utilizes and we'd like to get back to the main trunk as soon as possible.