Implement the rest of the mountable GDaemonFile ops:
   unmount_mountable
   eject_mountable

implement readahead in GVFSReadStream, time difference

implement seek & truncate

implement get_file_info for GFileInputStreamDaemon, needs marshalling attributes over custom protocol

finish implementing copy progress callbacks

implement stuff in GDaemonVolume / GDaemonVolumeMonitor

convert GDaemonFiles to fuse paths on request

detect fuse paths and reverse map back to GDaemonFile

remove owners from bus_name_map when they fail

smb support for smbc_getxattr!
smb - handle server going down

add trash:/// support 

decide exactly how to handle not-mounted errors and make sure its consistent.
mount daemons should re-register when new owner for vfs daemon.

Make built-in uri parsers link into gvfs shared lib instead of using a module
 (smb is a shared lib atm to make sure that works)

Implement GFileCreateFlags in backends as possible