FUSE options: enable `hard_remove`

This would prevent unlinked open files from persisting during the lifetime of the disorderfs overlay.

⚠ As mentioned in the Debian bug #1093768, there are FUSE-related side-effects on subsequent syscalls to unlinked, open files. So this might not be a great idea, but I thought it may be worth preparing the modification even so.

Edit: remove newline, add Debian bug hyperlink, and also remove the 'Closes' clause from this description because this isn't a Debian package codebase.