Genie:  Explicitly include vfs/node_ptr.hh
vfs:  Store raw node* in filehandle
vfs:  Elide <cstddef> include from filehandle.hh
Genie:  Normalize invocant as "that"
Genie:  Axe explicit shadow_filehandle destructor
Genie:  Rewrite shadow_filehandle
Genie -> vfs:  shadow_filehandle -> new_shadow()
Merge branch 'shadow'