CDEmu daemon

This is CDEmu daemon, the userspace daemon part of the userspace-cdemu suite, a
free, GPL CD/DVD-ROM device emulator for linux.

It receives SCSI commands from kernel module and processes them, passing the
requested data back to the kernel. Daemon implements the actual virtual device;
one instance per each device registered by kernel module. It uses libMirage, an
image access library that is part of userspace-cdemu suite, for the image access
(e.g. sector reading).

The daemon registers itself on D-BUS' system or session bus (depending on the
options passed to it) where it exposes an interface that can be used by clients
to control it.