Allow nfs_lookuppath_async to have path[0]=='\0'  this happens when we
want to create an object straight under the root directory of what we
mounted.
As always, the actual object to create is then a string starting after the \0 byte
Fix a bug when returning the filehandle in creat()  and return the filehandle
of the object we created and not the filehandle of the parent directory
Add two more examples:   nfs-ls  and nfs-cp