drive-menu: add the possibility to hide some items
Context: on my system, I have a few sshfs and cifs (samba) mounts. Those mounts do appear in the list of "drives" that can be unmounted and "ejected".
I can understand that some people may want to be able to unmount such locations, but this is not my case: they are really long-lived, and there is no reason they get unmounted during the session.
Whishlist: add an option to hide specific locations.