Draft: Allow pass-though of object type 3 (image file)
If an filing system presents FileSwitch with an object of type 3 (image) FileSwitch will not attach an image filing system.
This is done using an extra bit of the object type to internally indicate an object is an image and mask it off before return to callers.
Tested with IXFS in Linux port where it is used to represent symbolic links to directories. Can also be used in Network filing systems to allow concurrent access to images form multiple clients by running the ImageFS on the server.