MountAPIVFS= implicitly mounts /run as tmpfs now, no need to do this
explicitly.
The notification socket is now implicitly mounted too, if NotifyAccess=
and RootImage=/RootDirectory= are used together.
This adds a small service "systemd-portabled" and a matching client
"portablectl", which implement the "portable service" concept.
The daemon implements the actual operations, is PolicyKit-enabled and is
activated on demand with exit-on-idle.
Both the daemon and the client are an optional build artifact, enabled
by default rhough.
Lennart Poettering